Added basic support for IMAP CONDSTORE extension.

Process CAPABILITY in IMAP greeting response.
Renamed getUniqueId() to getUID() for consistency.

29 files changed, 1560 insertions, 450 deletions

diff --git a/SConstruct b/SConstruct
index 6f8b83ac..e4f149f3 100644
--- a/SConstruct
+++ b/SConstruct
@@ -204,6 +204,7 @@ libvmime_messaging_sources = [
 	'net/defaultConnectionInfos.cpp', 'net/defaultConnectionInfos.hpp',
 	'net/events.cpp', 'net/events.hpp',
 	'net/folder.cpp', 'net/folder.hpp',
+	'net/folderStatus.hpp',
 	'net/message.cpp', 'net/message.hpp',
 	'net/securedConnectionInfos.hpp',
 	'net/service.cpp', 'net/service.hpp',
@@ -245,6 +246,7 @@ libvmime_messaging_proto_sources = [
 			'net/pop3/POP3Store.cpp',        'net/pop3/POP3Store.hpp',
 			'net/pop3/POP3SStore.cpp',       'net/pop3/POP3SStore.hpp',
 			'net/pop3/POP3Folder.cpp',       'net/pop3/POP3Folder.hpp',
+			'net/pop3/POP3FolderStatus.cpp', 'net/pop3/POP3FolderStatus.hpp',
 			'net/pop3/POP3Message.cpp',      'net/pop3/POP3Message.hpp',
 			'net/pop3/POP3Response.cpp',     'net/pop3/POP3Response.hpp',
 			'net/pop3/POP3Utils.cpp',        'net/pop3/POP3Utils.hpp'
@@ -271,6 +273,7 @@ libvmime_messaging_proto_sources = [
 			'net/imap/IMAPStore.cpp',        'net/imap/IMAPStore.hpp',
 			'net/imap/IMAPSStore.cpp',       'net/imap/IMAPSStore.hpp',
 			'net/imap/IMAPFolder.cpp',       'net/imap/IMAPFolder.hpp',
+			'net/imap/IMAPFolderStatus.cpp', 'net/imap/IMAPFolderStatus.hpp',
 			'net/imap/IMAPMessage.cpp',      'net/imap/IMAPMessage.hpp',
 			'net/imap/IMAPTag.cpp',          'net/imap/IMAPTag.hpp',
 			'net/imap/IMAPUtils.cpp',        'net/imap/IMAPUtils.hpp',
@@ -286,6 +289,7 @@ libvmime_messaging_proto_sources = [
 			'net/maildir/maildirServiceInfos.cpp', 'net/maildir/maildirServiceInfos.hpp',
 			'net/maildir/maildirStore.cpp',        'net/maildir/maildirStore.hpp',
 			'net/maildir/maildirFolder.cpp',       'net/maildir/maildirFolder.hpp',
+			'net/maildir/maildirFolderStatus.cpp', 'net/maildir/maildirFolderStatus.hpp',
 			'net/maildir/maildirMessage.cpp',      'net/maildir/maildirMessage.hpp',
 			'net/maildir/maildirUtils.cpp',        'net/maildir/maildirUtils.hpp',
 			'net/maildir/maildirFormat.cpp',       'net/maildir/maildirFormat.hpp',
diff --git a/src/net/imap/IMAPConnection.cpp b/src/net/imap/IMAPConnection.cpp
index 935de8cf..c5ff58a7 100644
--- a/src/net/imap/IMAPConnection.cpp
+++ b/src/net/imap/IMAPConnection.cpp
@@ -35,6 +35,8 @@
 #include "vmime/exception.hpp"
 #include "vmime/platform.hpp"
 
+#include "vmime/utility/stringUtils.hpp"
+
 #include "vmime/net/defaultConnectionInfos.hpp"
 
 #if VMIME_HAVE_SASL_SUPPORT
@@ -66,7 +68,7 @@ namespace imap {
 IMAPConnection::IMAPConnection(ref <IMAPStore> store, ref <security::authenticator> auth)
 	: m_store(store), m_auth(auth), m_socket(NULL), m_parser(NULL), m_tag(NULL),
 	  m_hierarchySeparator('\0'), m_state(STATE_NONE), m_timeoutHandler(NULL),
-	  m_secured(false), m_firstTag(true), m_capabilitiesFetched(false)
+	  m_secured(false), m_firstTag(true), m_capabilitiesFetched(false), m_noModSeq(false)
 {
 }
 
@@ -155,6 +157,12 @@ void IMAPConnection::connect()
 		needAuth = true;
 	}
 
+	if (greet->resp_cond_auth()->resp_text()->resp_text_code() &&
+	    greet->resp_cond_auth()->resp_text()->resp_text_code()->capability_data())
+	{
+		processCapabilityResponseData(greet->resp_cond_auth()->resp_text()->resp_text_code()->capability_data());
+	}
+
 #if VMIME_HAVE_TLS_SUPPORT
 	// Setup secured connection, if requested
 	const bool tls = HAS_PROPERTY(PROPERTY_CONNECTION_TLS)
@@ -266,6 +274,10 @@ void IMAPConnection::authenticate()
 		internalDisconnect();
 		throw exceptions::authentication_error(m_parser->lastLine());
 	}
+
+	// Server capabilities may change when logged in
+	if (!processCapabilityResponseData(resp))
+		invalidateCapabilities();
 }
 
 
@@ -397,6 +409,9 @@ void IMAPConnection::authenticateSASL()
 
 					// Send response
 					send(false, saslContext->encodeB64(resp, respLen), true);
+
+					// Server capabilities may change when logged in
+					invalidateCapabilities();
 				}
 				catch (exceptions::sasl_exception& e)
 				{
@@ -506,6 +521,23 @@ const std::vector <string> IMAPConnection::getCapabilities()
 }
 
 
+bool IMAPConnection::hasCapability(const string& capa)
+{
+	if (!m_capabilitiesFetched)
+		fetchCapabilities();
+
+	const string normCapa = utility::stringUtils::toUpper(capa);
+
+	for (unsigned int i = 0, n = m_capabilities.size() ; i < n ; ++i)
+	{
+		if (m_capabilities[i] == normCapa)
+			return true;
+	}
+
+	return false;
+}
+
+
 void IMAPConnection::invalidateCapabilities()
 {
 	m_capabilities.clear();
@@ -519,35 +551,50 @@ void IMAPConnection::fetchCapabilities()
 
 	utility::auto_ptr <IMAPParser::response> resp(m_parser->readResponse());
 
-	std::vector <string> res;
-
 	if (resp->response_done()->response_tagged()->
 		resp_cond_state()->status() == IMAPParser::resp_cond_state::OK)
 	{
-		const std::vector <IMAPParser::continue_req_or_response_data*>& respDataList =
-			resp->continue_req_or_response_data();
+		processCapabilityResponseData(resp);
+	}
+}
 
-		for (unsigned int i = 0 ; i < respDataList.size() ; ++i)
-		{
-			if (respDataList[i]->response_data() == NULL)
-				continue;
 
-			const IMAPParser::capability_data* capaData =
-				respDataList[i]->response_data()->capability_data();
+bool IMAPConnection::processCapabilityResponseData(const IMAPParser::response* resp)
+{
+	const std::vector <IMAPParser::continue_req_or_response_data*>& respDataList =
+		resp->continue_req_or_response_data();
+
+	for (unsigned int i = 0 ; i < respDataList.size() ; ++i)
+	{
+		if (respDataList[i]->response_data() == NULL)
+			continue;
 
-			if (capaData == NULL)
-				continue;
+		const IMAPParser::capability_data* capaData =
+			respDataList[i]->response_data()->capability_data();
 
-			std::vector <IMAPParser::capability*> caps = capaData->capabilities();
+		if (capaData == NULL)
+			continue;
 
-			for (unsigned int j = 0 ; j < caps.size() ; ++j)
-			{
-				if (caps[j]->auth_type())
-					res.push_back("AUTH=" + caps[j]->auth_type()->name());
-				else
-					res.push_back(caps[j]->atom()->value());
-			}
-		}
+		processCapabilityResponseData(capaData);
+		return true;
+	}
+
+	return false;
+}
+
+
+void IMAPConnection::processCapabilityResponseData(const IMAPParser::capability_data* capaData)
+{
+	std::vector <string> res;
+
+	std::vector <IMAPParser::capability*> caps = capaData->capabilities();
+
+	for (unsigned int j = 0 ; j < caps.size() ; ++j)
+	{
+		if (caps[j]->auth_type())
+			res.push_back("AUTH=" + caps[j]->auth_type()->name());
+		else
+			res.push_back(utility::stringUtils::toUpper(caps[j]->atom()->value()));
 	}
 
 	m_capabilities = res;
@@ -756,6 +803,18 @@ ref <const socket> IMAPConnection::getSocket() const
 }
 
 
+bool IMAPConnection::isMODSEQDisabled() const
+{
+	return m_noModSeq;
+}
+
+
+void IMAPConnection::disableMODSEQ()
+{
+	m_noModSeq = true;
+}
+
+
 } // imap
 } // net
 } // vmime
diff --git a/src/net/imap/IMAPFolder.cpp b/src/net/imap/IMAPFolder.cpp
index 1ee8ac3f..3c54bce8 100644
--- a/src/net/imap/IMAPFolder.cpp
+++ b/src/net/imap/IMAPFolder.cpp
@@ -34,6 +34,7 @@
 #include "vmime/net/imap/IMAPMessage.hpp"
 #include "vmime/net/imap/IMAPUtils.hpp"
 #include "vmime/net/imap/IMAPConnection.hpp"
+#include "vmime/net/imap/IMAPFolderStatus.hpp"
 
 #include "vmime/message.hpp"
 
@@ -57,6 +58,8 @@ IMAPFolder::IMAPFolder(const folder::path& path, ref <IMAPStore> store, const in
 	  m_open(false), m_type(type), m_flags(flags), m_messageCount(0), m_uidValidity(0)
 {
 	store->registerFolder(this);
+
+	m_status = vmime::create <IMAPFolderStatus>();
 }
 
 
@@ -176,6 +179,9 @@ void IMAPFolder::open(const int mode, bool failIfModeIsNotAvailable)
 		oss << IMAPUtils::quoteString(IMAPUtils::pathToString
 				(connection->hierarchySeparator(), getFullPath()));
 
+		if (m_connection->hasCapability("CONDSTORE"))
+			oss << " (CONDSTORE)";
+
 		connection->send(true, oss.str(), true);
 
 		// Read the response
@@ -217,6 +223,11 @@ void IMAPFolder::open(const int mode, bool failIfModeIsNotAvailable)
 						m_uidValidity = static_cast <unsigned int>(code->nz_number()->value());
 						break;
 
+					case IMAPParser::resp_text_code::NOMODSEQ:
+
+						connection->disableMODSEQ();
+						break;
+
 					default:
 
 						break;
@@ -255,6 +266,8 @@ void IMAPFolder::open(const int mode, bool failIfModeIsNotAvailable)
 			}
 		}
 
+		processStatusUpdate(resp);
+
 		// Check for access mode (read-only or read-write)
 		const IMAPParser::resp_text_code* respTextCode = resp->response_done()->
 			response_tagged()->resp_cond_state()->resp_text()->resp_text_code();
@@ -792,7 +805,7 @@ void IMAPFolder::fetchMessages(std::vector <ref <message> >& msg, const int opti
 	}
 
 	// Send the request
-	const string command = IMAPUtils::buildFetchRequest(list, options);
+	const string command = IMAPUtils::buildFetchRequest(m_connection, list, options);
 	m_connection->send(true, command, true);
 
 	// Get the response
@@ -856,19 +869,17 @@ void IMAPFolder::fetchMessages(std::vector <ref <message> >& msg, const int opti
 
 	if (progress)
 		progress->stop(total);
+
+	processStatusUpdate(resp);
 }
 
 
 void IMAPFolder::fetchMessage(ref <message> msg, const int options)
 {
-	ref <IMAPStore> store = m_store.acquire();
-
-	if (!store)
-		throw exceptions::illegal_state("Store disconnected");
-	else if (!isOpen())
-		throw exceptions::illegal_state("Folder not open");
+	std::vector <ref <message> > msgs;
+	msgs.push_back(msg);
 
-	msg.dynamicCast <IMAPMessage>()->fetch(thisRef().dynamicCast <IMAPFolder>(), options);
+	fetchMessages(msgs, options, /* progress */ NULL);
 }
 
 
@@ -973,6 +984,8 @@ void IMAPFolder::deleteMessage(const int num)
 		 events::messageChangedEvent::TYPE_FLAGS, nums);
 
 	notifyMessageChanged(event);
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1040,6 +1053,8 @@ void IMAPFolder::deleteMessages(const int from, const int to)
 		 events::messageChangedEvent::TYPE_FLAGS, nums);
 
 	notifyMessageChanged(event);
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1103,6 +1118,8 @@ void IMAPFolder::deleteMessages(const std::vector <int>& nums)
 		 events::messageChangedEvent::TYPE_FLAGS, list);
 
 	notifyMessageChanged(event);
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1311,6 +1328,8 @@ void IMAPFolder::setMessageFlags(const string& set, const int flags, const int m
 			throw exceptions::command_error("STORE",
 				m_connection->getParser()->lastLine(), "bad response");
 		}
+
+		processStatusUpdate(resp);
 	}
 }
 
@@ -1455,6 +1474,8 @@ void IMAPFolder::addMessage(utility::inputStream& is, const int size, const int
 			(*it)->notifyMessageCount(event);
 		}
 	}
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1545,6 +1566,8 @@ void IMAPFolder::expunge()
 			(*it)->notifyMessageCount(event);
 		}
 	}
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1624,6 +1647,8 @@ void IMAPFolder::rename(const folder::path& newPath)
 			(*it)->notifyFolder(event);
 		}
 	}
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1767,16 +1792,30 @@ void IMAPFolder::copyMessages(const string& set, const folder::path& dest)
 		throw exceptions::command_error("COPY",
 			m_connection->getParser()->lastLine(), "bad response");
 	}
+
+	processStatusUpdate(resp);
 }
 
 
 void IMAPFolder::status(int& count, int& unseen)
 {
-	ref <IMAPStore> store = m_store.acquire();
-
 	count = 0;
 	unseen = 0;
 
+	ref <folderStatus> status = getStatus();
+
+	count = status->getMessageCount();
+	unseen = status->getUnseenCount();
+}
+
+
+ref <folderStatus> IMAPFolder::getStatus()
+{
+	ref <IMAPStore> store = m_store.acquire();
+
+	if (!store)
+		throw exceptions::illegal_state("Store disconnected");
+
 	// Build the request text
 	std::ostringstream command;
 	command.imbue(std::locale::classic());
@@ -1784,7 +1823,14 @@ void IMAPFolder::status(int& count, int& unseen)
 	command << "STATUS ";
 	command << IMAPUtils::quoteString(IMAPUtils::pathToString
 			(m_connection->hierarchySeparator(), getFullPath()));
-	command << " (MESSAGES UNSEEN)";
+	command << " (";
+
+	command << "MESSAGES" << ' ' << "UNSEEN" << ' ' << "UIDNEXT" << ' ' << "UIDVALIDITY";
+
+	if (m_connection->hasCapability("CONDSTORE"))
+		command << ' ' << "HIGHESTMODSEQ";
+
+	command << ")";
 
 	// Send the request
 	m_connection->send(true, command.str(), true);
@@ -1805,81 +1851,47 @@ void IMAPFolder::status(int& count, int& unseen)
 	for (std::vector <IMAPParser::continue_req_or_response_data*>::const_iterator
 	     it = respDataList.begin() ; it != respDataList.end() ; ++it)
 	{
-		if ((*it)->response_data() == NULL)
-		{
-			throw exceptions::command_error("STATUS",
-				m_connection->getParser()->lastLine(), "invalid response");
-		}
-
-		const IMAPParser::response_data* responseData = (*it)->response_data();
-
-		if (responseData->mailbox_data() &&
-			responseData->mailbox_data()->type() == IMAPParser::mailbox_data::STATUS)
+		if ((*it)->response_data() != NULL)
 		{
-			const IMAPParser::status_att_list* statusAttList =
-				responseData->mailbox_data()->status_att_list();
+			const IMAPParser::response_data* responseData = (*it)->response_data();
 
-			for (std::vector <IMAPParser::status_att_val*>::const_iterator
-			     jt = statusAttList->values().begin() ; jt != statusAttList->values().end() ; ++jt)
+			if (responseData->mailbox_data() &&
+				responseData->mailbox_data()->type() == IMAPParser::mailbox_data::STATUS)
 			{
-				switch ((*jt)->type())
-				{
-				case IMAPParser::status_att_val::MESSAGES:
-
-					count = (*jt)->value_as_number()->value();
-					break;
-
-				case IMAPParser::status_att_val::UNSEEN:
-
-					unseen = (*jt)->value_as_number()->value();
-					break;
+				ref <IMAPFolderStatus> status = vmime::create <IMAPFolderStatus>();
+				status->updateFromResponse(responseData->mailbox_data());
 
-				default:
+				m_messageCount = status->getMessageCount();
+				m_uidValidity = status->getUIDValidity();
 
-					break;
-				}
+				return status;
 			}
 		}
 	}
 
-	// Notify message count changed (new messages)
-	if (m_messageCount != count)
-	{
-		const int oldCount = m_messageCount;
-
-		m_messageCount = count;
-
-		if (count > oldCount)
-		{
-			std::vector <int> nums;
-			nums.reserve(count - oldCount);
+	throw exceptions::command_error("STATUS",
+		m_connection->getParser()->lastLine(), "invalid response");
+}
 
-			for (int i = oldCount + 1, j = 0 ; i <= count ; ++i, ++j)
-				nums[j] = i;
 
-			events::messageCountEvent event
-				(thisRef().dynamicCast <folder>(),
-				 events::messageCountEvent::TYPE_ADDED, nums);
+void IMAPFolder::noop()
+{
+	ref <IMAPStore> store = m_store.acquire();
 
-			notifyMessageCount(event);
+	if (!store)
+		throw exceptions::illegal_state("Store disconnected");
 
-			// Notify folders with the same path
-			for (std::list <IMAPFolder*>::iterator it = store->m_folders.begin() ;
-			     it != store->m_folders.end() ; ++it)
-			{
-				if ((*it) != this && (*it)->getFullPath() == m_path)
-				{
-					(*it)->m_messageCount = count;
+	m_connection->send(true, "NOOP", true);
 
-					events::messageCountEvent event
-						((*it)->thisRef().dynamicCast <folder>(),
-						 events::messageCountEvent::TYPE_ADDED, nums);
+	utility::auto_ptr <IMAPParser::response> resp(m_connection->readResponse());
 
-					(*it)->notifyMessageCount(event);
-				}
-			}
-		}
+	if (resp->isBad() || resp->response_done()->response_tagged()->
+			resp_cond_state()->status() != IMAPParser::resp_cond_state::OK)
+	{
+		throw exceptions::command_error("NOOP", m_connection->getParser()->lastLine());
 	}
+
+	processStatusUpdate(resp);
 }
 
 
@@ -1939,6 +1951,39 @@ std::vector <int> IMAPFolder::getMessageNumbersStartingOnUID(const message::uid&
 }
 
 
+void IMAPFolder::processStatusUpdate(const IMAPParser::response* resp)
+{
+	// Process tagged response
+	if (resp->response_done() && resp->response_done()->response_tagged() &&
+	    resp->response_done()->response_tagged()
+	    	->resp_cond_state()->resp_text()->resp_text_code())
+	{
+		const IMAPParser::resp_text_code* code =
+			resp->response_done()->response_tagged()
+				->resp_cond_state()->resp_text()->resp_text_code();
+
+		m_status->updateFromResponse(code);
+	}
+
+	// Process untagged responses
+	for (std::vector <IMAPParser::continue_req_or_response_data*>::const_iterator
+	     it = resp->continue_req_or_response_data().begin() ;
+	     it != resp->continue_req_or_response_data().end() ; ++it)
+	{
+		if ((*it)->response_data() && (*it)->response_data()->resp_cond_state() &&
+		    (*it)->response_data()->resp_cond_state()->resp_text()->resp_text_code())
+		{
+			const IMAPParser::resp_text_code* code =
+				(*it)->response_data()->resp_cond_state()->resp_text()->resp_text_code();
+
+			m_status->updateFromResponse(code);
+		}
+	}
+
+	m_messageCount = m_status->getMessageCount();
+	m_uidValidity = m_status->getUIDValidity();
+}
+
 } // imap
 } // net
 } // vmime
diff --git a/src/net/imap/IMAPFolderStatus.cpp b/src/net/imap/IMAPFolderStatus.cpp
new file mode 100644
index 00000000..009f6ba4
--- /dev/null
+++ b/src/net/imap/IMAPFolderStatus.cpp
@@ -0,0 +1,158 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_IMAP
+
+
+#include "vmime/net/imap/IMAPFolderStatus.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace imap {
+
+
+unsigned int IMAPFolderStatus::getMessageCount() const
+{
+	return m_count;
+}
+
+
+unsigned int IMAPFolderStatus::getUnseenCount() const
+{
+	return m_unseen;
+}
+
+
+unsigned int IMAPFolderStatus::getRecentCount() const
+{
+	return m_recent;
+}
+
+
+vmime_uint32 IMAPFolderStatus::getUIDValidity() const
+{
+	return m_uidValidity;
+}
+
+
+vmime_uint32 IMAPFolderStatus::getUIDNext() const
+{
+	return m_uidNext;
+}
+
+
+vmime_uint64 IMAPFolderStatus::getHighestModSeq() const
+{
+	return m_highestModSeq;
+}
+
+
+void IMAPFolderStatus::updateFromResponse(const IMAPParser::mailbox_data* resp)
+{
+	const IMAPParser::status_att_list* statusAttList = resp->status_att_list();
+
+	for (std::vector <IMAPParser::status_att_val*>::const_iterator
+		 jt = statusAttList->values().begin() ; jt != statusAttList->values().end() ; ++jt)
+	{
+		switch ((*jt)->type())
+		{
+		case IMAPParser::status_att_val::MESSAGES:
+
+			m_count = (*jt)->value_as_number()->value();
+			break;
+
+		case IMAPParser::status_att_val::UNSEEN:
+
+			m_unseen = (*jt)->value_as_number()->value();
+			break;
+
+		case IMAPParser::status_att_val::RECENT:
+
+			m_recent = (*jt)->value_as_number()->value();
+			break;
+
+		case IMAPParser::status_att_val::UIDNEXT:
+
+			m_uidNext = (*jt)->value_as_number()->value();
+			break;
+
+		case IMAPParser::status_att_val::UIDVALIDITY:
+
+			m_uidValidity = (*jt)->value_as_number()->value();
+			break;
+
+		case IMAPParser::status_att_val::HIGHESTMODSEQ:
+
+			m_highestModSeq = (*jt)->value_as_mod_sequence_value()->value();
+			break;
+		}
+	}
+}
+
+
+void IMAPFolderStatus::updateFromResponse(const IMAPParser::resp_text_code* resp)
+{
+	switch (resp->type())
+	{
+	case IMAPParser::resp_text_code::UIDVALIDITY:
+
+		m_uidValidity = resp->nz_number()->value();
+		break;
+
+	case IMAPParser::resp_text_code::UIDNEXT:
+
+		m_uidNext = resp->nz_number()->value();
+		break;
+
+	case IMAPParser::resp_text_code::UNSEEN:
+
+		m_unseen = resp->nz_number()->value();
+		break;
+
+	case IMAPParser::resp_text_code::HIGHESTMODSEQ:
+
+		m_highestModSeq = resp->mod_sequence_value()->value();
+		break;
+
+	case IMAPParser::resp_text_code::NOMODSEQ:
+
+		m_highestModSeq = 0;
+		break;
+
+	default:
+
+		break;
+	}
+}
+
+
+} // imap
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_IMAP
diff --git a/src/net/imap/IMAPMessage.cpp b/src/net/imap/IMAPMessage.cpp
index 6db00768..7e88ef85 100644
--- a/src/net/imap/IMAPMessage.cpp
+++ b/src/net/imap/IMAPMessage.cpp
@@ -98,15 +98,15 @@ private:
 
 IMAPMessage::IMAPMessage(ref <IMAPFolder> folder, const int num)
 	: m_folder(folder), m_num(num), m_size(-1), m_flags(FLAG_UNDEFINED),
-	  m_expunged(false), m_structure(NULL)
+	  m_expunged(false), m_modseq(0), m_structure(NULL)
 {
 	folder->registerMessage(this);
 }
 
 
-IMAPMessage::IMAPMessage(ref <IMAPFolder> folder, const int num, const uid& uniqueId)
+IMAPMessage::IMAPMessage(ref <IMAPFolder> folder, const int num, const uid& uid)
 	: m_folder(folder), m_num(num), m_size(-1), m_flags(FLAG_UNDEFINED),
-	  m_expunged(false), m_uid(uniqueId), m_structure(NULL)
+	  m_expunged(false), m_uid(uid), m_modseq(0), m_structure(NULL)
 {
 	folder->registerMessage(this);
 }
@@ -133,9 +133,15 @@ int IMAPMessage::getNumber() const
 }
 
 
-const message::uid IMAPMessage::getUniqueId() const
+const message::uid IMAPMessage::getUID() const
 {
-	return (m_uid);
+	return m_uid;
+}
+
+
+vmime_uint64 IMAPMessage::getModSequence() const
+{
+	return m_modseq;
 }
 
 
@@ -358,59 +364,6 @@ void IMAPMessage::extractImpl(ref <const part> p, utility::outputStream& os,
 }
 
 
-void IMAPMessage::fetch(ref <IMAPFolder> msgFolder, const int options)
-{
-	ref <IMAPFolder> folder = m_folder.acquire();
-
-	if (folder != msgFolder)
-		throw exceptions::folder_not_found();
-
-	// Send the request
-	std::vector <int> list;
-	list.push_back(m_num);
-
-	const string command = IMAPUtils::buildFetchRequest(list, options);
-
-	folder->m_connection->send(true, command, true);
-
-	// Get the response
-	utility::auto_ptr <IMAPParser::response> resp(folder->m_connection->readResponse());
-
-	if (resp->isBad() || resp->response_done()->response_tagged()->
-		resp_cond_state()->status() != IMAPParser::resp_cond_state::OK)
-	{
-		throw exceptions::command_error("FETCH",
-			folder->m_connection->getParser()->lastLine(), "bad response");
-	}
-
-	const std::vector <IMAPParser::continue_req_or_response_data*>& respDataList =
-		resp->continue_req_or_response_data();
-
-	for (std::vector <IMAPParser::continue_req_or_response_data*>::const_iterator
-	     it = respDataList.begin() ; it != respDataList.end() ; ++it)
-	{
-		if ((*it)->response_data() == NULL)
-		{
-			throw exceptions::command_error("FETCH",
-				folder->m_connection->getParser()->lastLine(), "invalid response");
-		}
-
-		const IMAPParser::message_data* messageData =
-			(*it)->response_data()->message_data();
-
-		// We are only interested in responses of type "FETCH"
-		if (messageData == NULL || messageData->type() != IMAPParser::message_data::FETCH)
-			continue;
-
-		if (static_cast <int>(messageData->number()) != m_num)
-			continue;
-
-		// Process fetch response for this message
-		processFetchResponse(options, messageData);
-	}
-}
-
-
 void IMAPMessage::processFetchResponse
 	(const int options, const IMAPParser::message_data* msgData)
 {
@@ -436,6 +389,11 @@ void IMAPMessage::processFetchResponse
 			m_uid = IMAPUtils::makeGlobalUID(folder->m_uidValidity, (*it)->unique_id()->value());
 			break;
 		}
+		case IMAPParser::msg_att_item::MODSEQ:
+		{
+			m_modseq = (*it)->mod_sequence_value()->value();
+			break;
+		}
 		case IMAPParser::msg_att_item::ENVELOPE:
 		{
 			if (!(options & folder::FETCH_FULL_HEADER))
@@ -731,7 +689,11 @@ ref <vmime::message> IMAPMessage::getParsedMessage()
 	}
 	catch (exceptions::unfetched_object&)
 	{
-		fetch(m_folder.acquire(), IMAPFolder::FETCH_STRUCTURE);
+		std::vector <ref <message> > msgs;
+		msgs.push_back(thisRef().dynamicCast <IMAPMessage>());
+
+		m_folder.acquire()->fetchMessages(msgs, IMAPFolder::FETCH_STRUCTURE, /* progress */ NULL);
+
 		structure = getStructure();
 	}
 
diff --git a/src/net/imap/IMAPStore.cpp b/src/net/imap/IMAPStore.cpp
index 1821b221..e8778f90 100644
--- a/src/net/imap/IMAPStore.cpp
+++ b/src/net/imap/IMAPStore.cpp
@@ -153,6 +153,12 @@ ref <connectionInfos> IMAPStore::getConnectionInfos() const
 }
 
 
+ref <IMAPConnection> IMAPStore::getConnection()
+{
+	return m_connection;
+}
+
+
 void IMAPStore::disconnect()
 {
 	if (!isConnected())
@@ -187,6 +193,13 @@ void IMAPStore::noop()
 	{
 		throw exceptions::command_error("NOOP", m_connection->getParser()->lastLine());
 	}
+
+
+	for (std::list <IMAPFolder*>::iterator it = m_folders.begin() ;
+	     it != m_folders.end() ; ++it)
+	{
+		(*it)->noop();
+	}
 }
 
 
diff --git a/src/net/imap/IMAPUtils.cpp b/src/net/imap/IMAPUtils.cpp
index 4fea517f..2aad06a1 100644
--- a/src/net/imap/IMAPUtils.cpp
+++ b/src/net/imap/IMAPUtils.cpp
@@ -634,7 +634,7 @@ const string IMAPUtils::dateTime(const vmime::datetime& date)
 
 // static
 const string IMAPUtils::buildFetchRequestImpl
-	(const string& mode, const string& set, const int options)
+	(ref <IMAPConnection> cnt, const string& mode, const string& set, const int options)
 {
 	// Example:
 	//   C: A654 FETCH 2:4 (FLAGS BODY[HEADER.FIELDS (DATE FROM)])
@@ -655,8 +655,14 @@ const string IMAPUtils::buildFetchRequestImpl
 		items.push_back("BODYSTRUCTURE");
 
 	if (options & folder::FETCH_UID)
+	{
 		items.push_back("UID");
 
+		// Also fetch MODSEQ if CONDSTORE is supported
+		if (cnt->hasCapability("CONDSTORE") && !cnt->isMODSEQDisabled())
+			items.push_back("MODSEQ");
+	}
+
 	if (options & folder::FETCH_FULL_HEADER)
 		items.push_back("RFC822.HEADER");
 	else
@@ -715,16 +721,18 @@ const string IMAPUtils::buildFetchRequestImpl
 
 
 // static
-const string IMAPUtils::buildFetchRequest(const std::vector <int>& list, const int options)
+const string IMAPUtils::buildFetchRequest
+	(ref <IMAPConnection> cnt, const std::vector <int>& list, const int options)
 {
-	return buildFetchRequestImpl("number", listToSet(list, -1, false), options);
+	return buildFetchRequestImpl(cnt, "number", listToSet(list, -1, false), options);
 }
 
 
 // static
-const string IMAPUtils::buildFetchRequest(const std::vector <message::uid>& list, const int options)
+const string IMAPUtils::buildFetchRequest
+	(ref <IMAPConnection> cnt, const std::vector <message::uid>& list, const int options)
 {
-	return buildFetchRequestImpl("uid", listToSet(list), options);
+	return buildFetchRequestImpl(cnt, "uid", listToSet(list), options);
 }
 
 
@@ -749,7 +757,7 @@ void IMAPUtils::convertAddressList
 
 
 // static
-unsigned int IMAPUtils::extractUIDFromGlobalUID(const message::uid& uid)
+vmime_uint32 IMAPUtils::extractUIDFromGlobalUID(const message::uid& uid)
 {
 	message::uid::size_type colonPos = uid.find(':');
 
@@ -758,7 +766,7 @@ unsigned int IMAPUtils::extractUIDFromGlobalUID(const message::uid& uid)
 		std::istringstream iss(uid);
 		iss.imbue(std::locale::classic());
 
-		unsigned int n = 0;
+		vmime_uint32 n = 0;
 		iss >> n;
 
 		return n;
@@ -768,7 +776,7 @@ unsigned int IMAPUtils::extractUIDFromGlobalUID(const message::uid& uid)
 		std::istringstream iss(uid.substr(colonPos + 1));
 		iss.imbue(std::locale::classic());
 
-		unsigned int n = 0;
+		vmime_uint32 n = 0;
 		iss >> n;
 
 		return n;
@@ -777,7 +785,7 @@ unsigned int IMAPUtils::extractUIDFromGlobalUID(const message::uid& uid)
 
 
 // static
-const message::uid IMAPUtils::makeGlobalUID(const unsigned int UIDValidity, const unsigned int messageUID)
+const message::uid IMAPUtils::makeGlobalUID(const vmime_uint32 UIDValidity, const vmime_uint32 messageUID)
 {
 	std::ostringstream oss;
 	oss.imbue(std::locale::classic());
diff --git a/src/net/maildir/maildirFolder.cpp b/src/net/maildir/maildirFolder.cpp
index aa886ff3..3ea1093e 100644
--- a/src/net/maildir/maildirFolder.cpp
+++ b/src/net/maildir/maildirFolder.cpp
@@ -33,6 +33,7 @@
 #include "vmime/net/maildir/maildirMessage.hpp"
 #include "vmime/net/maildir/maildirUtils.hpp"
 #include "vmime/net/maildir/maildirFormat.hpp"
+#include "vmime/net/maildir/maildirFolderStatus.hpp"
 
 #include "vmime/utility/smartPtr.hpp"
 
@@ -1163,22 +1164,36 @@ void maildirFolder::notifyMessagesCopied(const folder::path& dest)
 
 void maildirFolder::status(int& count, int& unseen)
 {
+	count = 0;
+	unseen = 0;
+
+	ref <folderStatus> status = getStatus();
+
+	count = status->getMessageCount();
+	unseen = status->getUnseenCount();
+}
+
+
+ref <folderStatus> maildirFolder::getStatus()
+{
 	ref <maildirStore> store = m_store.acquire();
 
 	const int oldCount = m_messageCount;
 
 	scanFolder();
 
-	count = m_messageCount;
-	unseen = m_unreadMessageCount;
+	ref <maildirFolderStatus> status = vmime::create <maildirFolderStatus>();
+
+	status->setMessageCount(m_messageCount);
+	status->setUnseenCount(m_unreadMessageCount);
 
 	// Notify message count changed (new messages)
-	if (count > oldCount)
+	if (m_messageCount > oldCount)
 	{
 		std::vector <int> nums;
-		nums.reserve(count - oldCount);
+		nums.reserve(m_messageCount - oldCount);
 
-		for (int i = oldCount + 1, j = 0 ; i <= count ; ++i, ++j)
+		for (int i = oldCount + 1, j = 0 ; i <= m_messageCount ; ++i, ++j)
 			nums[j] = i;
 
 		events::messageCountEvent event
@@ -1207,6 +1222,8 @@ void maildirFolder::status(int& count, int& unseen)
 			}
 		}
 	}
+
+	return status;
 }
 
 
diff --git a/src/net/maildir/maildirFolderStatus.cpp b/src/net/maildir/maildirFolderStatus.cpp
new file mode 100644
index 00000000..49425e59
--- /dev/null
+++ b/src/net/maildir/maildirFolderStatus.cpp
@@ -0,0 +1,67 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_MAILDIR
+
+
+#include "vmime/net/maildir/maildirFolderStatus.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace maildir {
+
+
+unsigned int maildirFolderStatus::getMessageCount() const
+{
+	return m_count;
+}
+
+
+unsigned int maildirFolderStatus::getUnseenCount() const
+{
+	return m_unseen;
+}
+
+
+void maildirFolderStatus::setMessageCount(const unsigned int count)
+{
+	m_count = count;
+}
+
+
+void maildirFolderStatus::setUnseenCount(const unsigned int unseen)
+{
+	m_unseen = unseen;
+}
+
+
+} // maildir
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_MAILDIR
diff --git a/src/net/maildir/maildirMessage.cpp b/src/net/maildir/maildirMessage.cpp
index 9b14ad78..b6c12053 100644
--- a/src/net/maildir/maildirMessage.cpp
+++ b/src/net/maildir/maildirMessage.cpp
@@ -261,7 +261,7 @@ int maildirMessage::getNumber() const
 }
 
 
-const message::uid maildirMessage::getUniqueId() const
+const message::uid maildirMessage::getUID() const
 {
 	return (m_uid);
 }
diff --git a/src/net/pop3/POP3Folder.cpp b/src/net/pop3/POP3Folder.cpp
index 7aa850b1..1b7b3df6 100644
--- a/src/net/pop3/POP3Folder.cpp
+++ b/src/net/pop3/POP3Folder.cpp
@@ -33,6 +33,7 @@
 #include "vmime/net/pop3/POP3Message.hpp"
 #include "vmime/net/pop3/POP3Command.hpp"
 #include "vmime/net/pop3/POP3Response.hpp"
+#include "vmime/net/pop3/POP3FolderStatus.hpp"
 
 #include "vmime/net/pop3/POP3Utils.hpp"
 
@@ -752,12 +753,22 @@ void POP3Folder::copyMessages(const folder::path& /* dest */, const std::vector
 
 void POP3Folder::status(int& count, int& unseen)
 {
+	count = 0;
+	unseen = 0;
+
+	ref <folderStatus> status = getStatus();
+
+	count = status->getMessageCount();
+	unseen = status->getUnseenCount();
+}
+
+
+ref <folderStatus> POP3Folder::getStatus()
+{
 	ref <POP3Store> store = m_store.acquire();
 
 	if (!store)
 		throw exceptions::illegal_state("Store disconnected");
-	else if (!isOpen())
-		throw exceptions::illegal_state("Folder not open");
 
 	POP3Command::STAT()->send(store->getConnection());
 
@@ -767,10 +778,16 @@ void POP3Folder::status(int& count, int& unseen)
 	if (!response->isSuccess())
 		throw exceptions::command_error("STAT", response->getFirstLine());
 
+
+	unsigned int count = 0;
+
 	std::istringstream iss(response->getText());
 	iss >> count;
 
-	unseen = count;
+	ref <POP3FolderStatus> status = vmime::create <POP3FolderStatus>();
+
+	status->setMessageCount(count);
+	status->setUnseenCount(count);
 
 	// Update local message count
 	if (m_messageCount != count)
@@ -811,6 +828,8 @@ void POP3Folder::status(int& count, int& unseen)
 			}
 		}
 	}
+
+	return status;
 }
 
 
diff --git a/src/net/pop3/POP3FolderStatus.cpp b/src/net/pop3/POP3FolderStatus.cpp
new file mode 100644
index 00000000..e8c5face
--- /dev/null
+++ b/src/net/pop3/POP3FolderStatus.cpp
@@ -0,0 +1,67 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_POP3
+
+
+#include "vmime/net/pop3/POP3FolderStatus.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace pop3 {
+
+
+unsigned int POP3FolderStatus::getMessageCount() const
+{
+	return m_count;
+}
+
+
+unsigned int POP3FolderStatus::getUnseenCount() const
+{
+	return m_unseen;
+}
+
+
+void POP3FolderStatus::setMessageCount(const unsigned int count)
+{
+	m_count = count;
+}
+
+
+void POP3FolderStatus::setUnseenCount(const unsigned int unseen)
+{
+	m_unseen = unseen;
+}
+
+
+} // pop3
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_POP3
diff --git a/src/net/pop3/POP3Message.cpp b/src/net/pop3/POP3Message.cpp
index d2bb9881..659e3d79 100644
--- a/src/net/pop3/POP3Message.cpp
+++ b/src/net/pop3/POP3Message.cpp
@@ -72,7 +72,7 @@ int POP3Message::getNumber() const
 }
 
 
-const message::uid POP3Message::getUniqueId() const
+const message::uid POP3Message::getUID() const
 {
 	return (m_uid);
 }
diff --git a/vmime/net/folder.hpp b/vmime/net/folder.hpp
index b34ff812..f65f3711 100644
--- a/vmime/net/folder.hpp
+++ b/vmime/net/folder.hpp
@@ -39,6 +39,7 @@
 #include "vmime/message.hpp"
 #include "vmime/net/message.hpp"
 #include "vmime/net/events.hpp"
+#include "vmime/net/folderStatus.hpp"
 
 #include "vmime/utility/path.hpp"
 #include "vmime/utility/stream.hpp"
@@ -335,12 +336,21 @@ public:
 
 	/** Request folder status without opening it.
 	  *
+	  * \deprecated Use the new getStatus() method
+	  *
 	  * @param count will receive the number of messages in the folder
 	  * @param unseen will receive the number of unseen messages in the folder
 	  * @throw net_exception if an error occurs
 	  */
 	virtual void status(int& count, int& unseen) = 0;
 
+	/** Request folder status without opening it.
+	  *
+	  * @return current folder status
+	  * @throw net_exception if an error occurs
+	  */
+	virtual ref <folderStatus> getStatus() = 0;
+
 	/** Expunge deleted messages.
 	  *
 	  * @throw net_exception if an error occurs
diff --git a/vmime/net/folderStatus.hpp b/vmime/net/folderStatus.hpp
new file mode 100644
index 00000000..90beea66
--- /dev/null
+++ b/vmime/net/folderStatus.hpp
@@ -0,0 +1,68 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#ifndef VMIME_NET_FOLDERSTATUS_HPP_INCLUDED
+#define VMIME_NET_FOLDERSTATUS_HPP_INCLUDED
+
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES
+
+
+#include "vmime/base.hpp"
+
+
+namespace vmime {
+namespace net {
+
+
+/** Holds the status of a mail store folder.
+  */
+
+class VMIME_EXPORT folderStatus : public object
+{
+public:
+
+	/** Returns the total number of messages in the folder.
+	  *
+	  * @return number of messages
+	  */
+	virtual unsigned int getMessageCount() const = 0;
+
+	/** Returns the number of unseen messages in the folder.
+	  *
+	  * @return number of unseen messages
+	  */
+	virtual unsigned int getUnseenCount() const = 0;
+};
+
+
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES
+
+#endif // VMIME_NET_FOLDERSTATUS_HPP_INCLUDED
diff --git a/vmime/net/imap/IMAPConnection.hpp b/vmime/net/imap/IMAPConnection.hpp
index 257e60d3..72defc29 100644
--- a/vmime/net/imap/IMAPConnection.hpp
+++ b/vmime/net/imap/IMAPConnection.hpp
@@ -96,6 +96,7 @@ public:
 	void fetchCapabilities();
 	void invalidateCapabilities();
 	const std::vector <string> getCapabilities();
+	bool hasCapability(const string& capa);
 
 	ref <security::authenticator> getAuthenticator();
 
@@ -104,6 +105,9 @@ public:
 
 	ref <const socket> getSocket() const;
 
+	bool isMODSEQDisabled() const;
+	void disableMODSEQ();
+
 private:
 
 	void authenticate();
@@ -115,6 +119,9 @@ private:
 	void startTLS();
 #endif // VMIME_HAVE_TLS_SUPPORT
 
+	bool processCapabilityResponseData(const IMAPParser::response* resp);
+	void processCapabilityResponseData(const IMAPParser::capability_data* capaData);
+
 
 	weak_ref <IMAPStore> m_store;
 
@@ -140,6 +147,8 @@ private:
 	std::vector <string> m_capabilities;
 	bool m_capabilitiesFetched;
 
+	bool m_noModSeq;
+
 
 	void internalDisconnect();
 
diff --git a/vmime/net/imap/IMAPFolder.hpp b/vmime/net/imap/IMAPFolder.hpp
index 55c16e9c..48e07603 100644
--- a/vmime/net/imap/IMAPFolder.hpp
+++ b/vmime/net/imap/IMAPFolder.hpp
@@ -38,6 +38,8 @@
 
 #include "vmime/net/folder.hpp"
 
+#include "vmime/net/imap/IMAPParser.hpp"
+
 
 namespace vmime {
 namespace net {
@@ -47,6 +49,7 @@ namespace imap {
 class IMAPStore;
 class IMAPMessage;
 class IMAPConnection;
+class IMAPFolderStatus;
 
 
 /** IMAP folder implementation.
@@ -62,7 +65,7 @@ private:
 
 
 	IMAPFolder(const folder::path& path, ref <IMAPStore> store, const int type = TYPE_UNDEFINED, const int flags = FLAG_UNDEFINED);
-	IMAPFolder(const IMAPFolder&) : folder() { }
+	IMAPFolder(const IMAPFolder&);
 
 	~IMAPFolder();
 
@@ -118,6 +121,9 @@ public:
 	void copyMessages(const folder::path& dest, const std::vector <int>& nums);
 
 	void status(int& count, int& unseen);
+	ref <folderStatus> getStatus();
+
+	void noop();
 
 	void expunge();
 
@@ -148,6 +154,18 @@ private:
 	void copyMessages(const string& set, const folder::path& dest);
 
 
+	/** Process status updates ("unsolicited responses") contained in the
+	  * specified response. Example:
+	  *
+	  *    C: a006 NOOP
+	  *    S: * 930 EXISTS       <-- this is a status update
+	  *    S: a006 OK Success
+	  *
+	  * @param resp parsed IMAP response
+	  */
+	void processStatusUpdate(const IMAPParser::response* resp);
+
+
 	weak_ref <IMAPStore> m_store;
 	ref <IMAPConnection> m_connection;
 
@@ -161,8 +179,8 @@ private:
 	int m_flags;
 
 	int m_messageCount;
-
-	unsigned int m_uidValidity;
+	vmime_uint32 m_uidValidity;
+	ref <IMAPFolderStatus> m_status;
 
 	std::vector <IMAPMessage*> m_messages;
 };
diff --git a/vmime/net/imap/IMAPFolderStatus.hpp b/vmime/net/imap/IMAPFolderStatus.hpp
new file mode 100644
index 00000000..1cad217c
--- /dev/null
+++ b/vmime/net/imap/IMAPFolderStatus.hpp
@@ -0,0 +1,117 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#ifndef VMIME_NET_IMAP_IMAPFOLDERSTATUS_HPP_INCLUDED
+#define VMIME_NET_IMAP_IMAPFOLDERSTATUS_HPP_INCLUDED
+
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_IMAP
+
+
+#include "vmime/net/folderStatus.hpp"
+
+#include "vmime/net/imap/IMAPParser.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace imap {
+
+
+/** Holds the status of an IMAP folder.
+  */
+
+class VMIME_EXPORT IMAPFolderStatus : public folderStatus
+{
+public:
+
+	// Inherited from folderStatus
+	unsigned int getMessageCount() const;
+	unsigned int getUnseenCount() const;
+
+	/** Returns the the number of messages with the Recent flag set.
+	  *
+	  * @return number of messages flagged Recent
+	  */
+	unsigned int getRecentCount() const;
+
+	/** Returns the UID validity of the folder for the current session.
+	  * If the server is capable of persisting UIDs accross sessions,
+	  * this value should never change for a folder.
+	  *
+	  * @return UID validity of the folder
+	  */
+	vmime_uint32 getUIDValidity() const;
+
+	/** Returns the UID value that will be assigned to a new message
+	  * in the folder. If the server does not support the UIDPLUS
+	  * extension, it will return 0.
+	  *
+	  * @return UID of the next message
+	  */
+	vmime_uint32 getUIDNext() const;
+
+	/** Returns the highest modification sequence of all messages
+	  * in the folder, or 0 if not available for this folder, or not
+	  * supported by the server. The server must support the CONDSTORE
+	  * extension for this to be available.
+	  *
+	  * @return highest modification sequence
+	  */
+	vmime_uint64 getHighestModSeq() const;
+
+
+	/** Reads the folder status from the specified IMAP response.
+	  *
+	  * @param resp parsed IMAP response
+	  */
+	void updateFromResponse(const IMAPParser::mailbox_data* resp);
+
+	/** Reads the folder status from the specified IMAP response.
+	  *
+	  * @param resp parsed IMAP response
+	  */
+	void updateFromResponse(const IMAPParser::resp_text_code* resp);
+
+private:
+
+	unsigned int m_count;
+	unsigned int m_unseen;
+	unsigned int m_recent;
+	vmime_uint32 m_uidValidity;
+	vmime_uint32 m_uidNext;
+	vmime_uint64 m_highestModSeq;
+};
+
+
+} // imap
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_IMAP
+
+#endif // VMIME_NET_IMAP_IMAPFOLDERSTATUS_HPP_INCLUDED
diff --git a/vmime/net/imap/IMAPMessage.hpp b/vmime/net/imap/IMAPMessage.hpp
index 5c36ce13..fb86696f 100644
--- a/vmime/net/imap/IMAPMessage.hpp
+++ b/vmime/net/imap/IMAPMessage.hpp
@@ -57,7 +57,7 @@ private:
 	friend class vmime::creator;  // vmime::create <IMAPMessage>
 
 	IMAPMessage(ref <IMAPFolder> folder, const int num);
-	IMAPMessage(ref <IMAPFolder> folder, const int num, const uid& uniqueId);
+	IMAPMessage(ref <IMAPFolder> folder, const int num, const uid& uid);
 	IMAPMessage(const IMAPMessage&) : message() { }
 
 	~IMAPMessage();
@@ -66,7 +66,19 @@ public:
 
 	int getNumber() const;
 
-	const uid getUniqueId() const;
+	const uid getUID() const;
+
+	/** Returns the modification sequence for this message.
+	  *
+	  * Every time metadata for this message changes, the modification
+	  * sequence is updated, and is greater than the previous one. The
+	  * server must support the CONDSTORE extension for this to be
+	  * available.
+	  *
+	  * @return modification sequence, or zero if not supported by
+	  * the underlying protocol
+	  */
+	vmime_uint64 getModSequence() const;
 
 	int getSize() const;
 
@@ -89,8 +101,6 @@ public:
 
 private:
 
-	void fetch(ref <IMAPFolder> folder, const int options);
-
 	void processFetchResponse(const int options, const IMAPParser::message_data* msgData);
 
 	/** Recursively fetch part header for all parts in the structure.
@@ -132,6 +142,7 @@ private:
 	int m_flags;
 	bool m_expunged;
 	uid m_uid;
+	vmime_uint64 m_modseq;
 
 	ref <header> m_header;
 	ref <structure> m_structure;
diff --git a/vmime/net/imap/IMAPParser.hpp b/vmime/net/imap/IMAPParser.hpp
index 41252a92..af871c27 100644
--- a/vmime/net/imap/IMAPParser.hpp
+++ b/vmime/net/imap/IMAPParser.hpp
@@ -1288,6 +1288,211 @@ public:
 	};
 
 
+	// seq-number      = nz-number / "*"
+	//                    ; message sequence number (COPY, FETCH, STORE
+	//                    ; commands) or unique identifier (UID COPY,
+	//                    ; UID FETCH, UID STORE commands).
+
+	class seq_number : public component
+	{
+	public:
+
+		seq_number()
+			: m_number(NULL), m_star(false)
+		{
+		}
+
+		~seq_number()
+		{
+			delete m_number;
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("seq_number");
+
+			string::size_type pos = *currentPos;
+
+			if (parser.check <one_char <'*'> >(line, &pos, true))
+			{
+				m_star = true;
+				m_number = NULL;
+			}
+			else
+			{
+				m_star = false;
+				m_number = parser.get <IMAPParser::number>(line, &pos);
+			}
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		IMAPParser::number* m_number;
+		bool m_star;
+
+	public:
+
+		const IMAPParser::number* number() const { return m_number; }
+		bool star() const { return m_star; }
+	};
+
+
+	// seq-range       = seq-number ":" seq-number
+	//                    ; two seq-number values and all values between
+	//                    ; these two regardless of order.
+	//                    ; Example: 2:4 and 4:2 are equivalent and indicate
+	//                    ; values 2, 3, and 4.
+
+	class seq_range : public component
+	{
+	public:
+
+		seq_range()
+			: m_first(NULL), m_last(NULL)
+		{
+		}
+
+		~seq_range()
+		{
+			delete m_first;
+			delete m_last;
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("seq_range");
+
+			string::size_type pos = *currentPos;
+
+			m_first = parser.get <seq_number>(line, &pos);
+
+			parser.check <one_char <'*'> >(line, &pos);
+
+			m_last = parser.get <seq_number>(line, &pos);
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		IMAPParser::seq_number* m_first;
+		IMAPParser::seq_number* m_last;
+
+	public:
+
+		const IMAPParser::seq_number* first() const { return m_first; }
+		const IMAPParser::seq_number* last() const { return m_last; }
+	};
+
+
+	// sequence-set    = (seq-number / seq-range) *("," sequence-set)
+	//                    ; set of seq-number values, regardless of order.
+	//                    ; Servers MAY coalesce overlaps and/or execute the
+	//                    ; sequence in any order.
+	//                    ; Example: a message sequence number set of
+	//                    ; 2,4:7,9,12:* for a mailbox with 15 messages is
+	//                    ; equivalent to 2,4,5,6,7,9,12,13,14,15
+
+	class sequence_set : public component
+	{
+	public:
+
+		sequence_set()
+			: m_number(NULL), m_range(NULL), m_nextSet(NULL)
+		{
+		}
+
+		~sequence_set()
+		{
+			delete m_number;
+			delete m_range;
+			delete m_nextSet;
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("sequence_set");
+
+			string::size_type pos = *currentPos;
+
+			if ((m_range = parser.get <IMAPParser::seq_range>(line, &pos, true)) == NULL)
+				m_number = parser.get <IMAPParser::seq_number>(line, &pos);
+
+			if (parser.check <one_char <','> >(line, &pos, true))
+				m_nextSet = parser.get <sequence_set>(line, &pos);
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		IMAPParser::seq_number* m_number;
+		IMAPParser::seq_range* m_range;
+		IMAPParser::sequence_set* m_nextSet;
+
+	public:
+
+		const IMAPParser::seq_number* seq_number() const { return m_number; }
+		const IMAPParser::seq_range* seq_range() const { return m_range; }
+		const IMAPParser::sequence_set* next_sequence_set() const { return m_nextSet; }
+	};
+
+
+	// mod-sequence-value  = 1*DIGIT
+	//                        ;; Positive unsigned 64-bit integer
+	//                        ;; (mod-sequence)
+	//                        ;; (1 <= n < 18,446,744,073,709,551,615)
+
+	class mod_sequence_value : public component
+	{
+	public:
+
+		mod_sequence_value()
+			: m_value(0)
+		{
+		}
+
+		void go(IMAPParser& /* parser */, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("mod_sequence_value");
+
+			string::size_type pos = *currentPos;
+
+			bool valid = true;
+			vmime_uint64 val = 0;
+
+			while (valid && pos < line.length())
+			{
+				const char c = line[pos];
+
+				if (c >= '0' && c <= '9')
+				{
+					val = (val * 10) + (c - '0');
+					++pos;
+				}
+				else
+				{
+					valid = false;
+				}
+			}
+
+			m_value = val;
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		vmime_uint64 m_value;
+
+	public:
+
+		const vmime_uint64 value() const { return m_value; }
+	};
+
+
 	//
 	// flag            ::= "\Answered" / "\Flagged" / "\Deleted" /
 	//                     "\Seen" / "\Draft" / flag_keyword / flag_extension
@@ -1666,249 +1871,6 @@ public:
 
 
 	//
-	// resp_text_code ::= "ALERT" / "PARSE" /
-	//                    "PERMANENTFLAGS" SPACE "(" #(flag / "\*") ")" /
-	//                    "READ-ONLY" / "READ-WRITE" / "TRYCREATE" /
-	//                    "UIDVALIDITY" SPACE nz_number /
-	//                    "UNSEEN" SPACE nz_number /
-	//                    atom [SPACE 1*<any TEXT_CHAR except "]">]
-
-	class resp_text_code : public component
-	{
-	public:
-
-		resp_text_code()
-			: m_nz_number(NULL), m_atom(NULL), m_flag_list(NULL), m_text(NULL)
-		{
-		}
-
-		~resp_text_code()
-		{
-			delete (m_nz_number);
-			delete (m_atom);
-			delete (m_flag_list);
-			delete (m_text);
-		}
-
-		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
-		{
-			DEBUG_ENTER_COMPONENT("resp_text_code");
-
-			string::size_type pos = *currentPos;
-
-			// "ALERT"
-			if (parser.checkWithArg <special_atom>(line, &pos, "alert", true))
-			{
-				m_type = ALERT;
-			}
-			// "PARSE"
-			else if (parser.checkWithArg <special_atom>(line, &pos, "parse", true))
-			{
-				m_type = PARSE;
-			}
-			// "PERMANENTFLAGS" SPACE flag_list
-			else if (parser.checkWithArg <special_atom>(line, &pos, "permanentflags", true))
-			{
-				m_type = PERMANENTFLAGS;
-
-				parser.check <SPACE>(line, &pos);
-
-				m_flag_list = parser.get <IMAPParser::flag_list>(line, &pos);
-			}
-			// "READ-ONLY"
-			else if (parser.checkWithArg <special_atom>(line, &pos, "read-only", true))
-			{
-				m_type = READ_ONLY;
-			}
-			// "READ-WRITE"
-			else if (parser.checkWithArg <special_atom>(line, &pos, "read-write", true))
-			{
-				m_type = READ_WRITE;
-			}
-			// "TRYCREATE"
-			else if (parser.checkWithArg <special_atom>(line, &pos, "trycreate", true))
-			{
-				m_type = TRYCREATE;
-			}
-			// "UIDVALIDITY" SPACE nz_number
-			else if (parser.checkWithArg <special_atom>(line, &pos, "uidvalidity", true))
-			{
-				m_type = UIDVALIDITY;
-
-				parser.check <SPACE>(line, &pos);
-				m_nz_number = parser.get <IMAPParser::nz_number>(line, &pos);
-			}
-			// "UNSEEN" SPACE nz_number
-			else if (parser.checkWithArg <special_atom>(line, &pos, "unseen", true))
-			{
-				m_type = UNSEEN;
-
-				parser.check <SPACE>(line, &pos);
-				m_nz_number = parser.get <IMAPParser::nz_number>(line, &pos);
-			}
-			// atom [SPACE 1*<any TEXT_CHAR except "]">]
-			else
-			{
-				m_type = OTHER;
-
-				m_atom = parser.get <IMAPParser::atom>(line, &pos);
-
-				if (parser.check <SPACE>(line, &pos, true))
-					m_text = parser.get <text_except <']'> >(line, &pos);
-			}
-
-			*currentPos = pos;
-		}
-
-
-		enum Type
-		{
-			ALERT,
-			PARSE,
-			PERMANENTFLAGS,
-			READ_ONLY,
-			READ_WRITE,
-			TRYCREATE,
-			UIDVALIDITY,
-			UNSEEN,
-			OTHER
-		};
-
-	private:
-
-		Type m_type;
-
-		IMAPParser::nz_number* m_nz_number;
-		IMAPParser::atom* m_atom;
-		IMAPParser::flag_list* m_flag_list;
-		IMAPParser::text* m_text;
-
-	public:
-
-		Type type() const { return (m_type); }
-
-		const IMAPParser::nz_number* nz_number() const { return (m_nz_number); }
-		const IMAPParser::atom* atom() const { return (m_atom); }
-		const IMAPParser::flag_list* flag_list() const { return (m_flag_list); }
-		const IMAPParser::text* text() const { return (m_text); }
-	};
-
-
-	//
-	// resp_text ::= ["[" resp_text_code "]" SPACE] (text_mime2 / text)
-	//               ;; text SHOULD NOT begin with "[" or "="
-
-	class resp_text : public component
-	{
-	public:
-
-		resp_text()
-			: m_resp_text_code(NULL)
-		{
-		}
-
-		~resp_text()
-		{
-			delete (m_resp_text_code);
-		}
-
-		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
-		{
-			DEBUG_ENTER_COMPONENT("resp_text");
-
-			string::size_type pos = *currentPos;
-
-			if (parser.check <one_char <'['> >(line, &pos, true))
-			{
-				m_resp_text_code = parser.get <IMAPParser::resp_text_code>(line, &pos);
-
-				parser.check <one_char <']'> >(line, &pos);
-				parser.check <SPACE>(line, &pos, true);
-			}
-
-			text_mime2* text1 = parser.get <text_mime2>(line, &pos, true);
-
-			if (text1 != NULL)
-			{
-				m_text = text1->value();
-				delete (text1);
-			}
-			else
-			{
-				IMAPParser::text* text2 =
-					parser.get <IMAPParser::text>(line, &pos, true);
-
-				if (text2 != NULL)
-				{
-					m_text = text2->value();
-					delete (text2);
-				}
-				else
-				{
-					// Empty response text
-				}
-			}
-
-			*currentPos = pos;
-		}
-
-	private:
-
-		IMAPParser::resp_text_code* m_resp_text_code;
-		string m_text;
-
-	public:
-
-		const IMAPParser::resp_text_code* resp_text_code() const { return (m_resp_text_code); }
-		const string& text() const { return (m_text); }
-	};
-
-
-	//
-	// continue_req   ::= "+" SPACE (resp_text / base64)
-	//
-
-	class continue_req : public component
-	{
-	public:
-
-		continue_req()
-			: m_resp_text(NULL)
-		{
-		}
-
-		~continue_req()
-		{
-			delete (m_resp_text);
-		}
-
-		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
-		{
-			DEBUG_ENTER_COMPONENT("continue_req");
-
-			string::size_type pos = *currentPos;
-
-			parser.check <one_char <'+'> >(line, &pos);
-			parser.check <SPACE>(line, &pos);
-
-			m_resp_text = parser.get <IMAPParser::resp_text>(line, &pos);
-
-			parser.check <CRLF>(line, &pos);
-
-			*currentPos = pos;
-		}
-
-	private:
-
-		IMAPParser::resp_text* m_resp_text;
-
-	public:
-
-		const IMAPParser::resp_text* resp_text() const { return (m_resp_text); }
-	};
-
-
-	//
 	// auth_type ::= atom
 	//               ;; Defined by [IMAP-AUTH]
 	//
@@ -1965,6 +1927,13 @@ public:
 	//                   ("UIDVALIDITY" SP nz-number) /
 	//                   ("UNSEEN" SP number)
 	//
+	// IMAP Extension for Conditional STORE (RFC-4551):
+	//
+	//   status-att-val      =/ "HIGHESTMODSEQ" SP mod-sequence-valzer
+	//                          ;; extends non-terminal defined in [IMAPABNF].
+	//                          ;; Value 0 denotes that the mailbox doesn't
+	//                          ;; support persistent mod-sequences
+	//
 
 	class status_att_val : public component
 	{
@@ -1976,30 +1945,41 @@ public:
 
 			string::size_type pos = *currentPos;
 
-			if (parser.checkWithArg <special_atom>(line, &pos, "messages", true))
-			{
-				m_type = MESSAGES;
-			}
-			else if (parser.checkWithArg <special_atom>(line, &pos, "recent", true))
-			{
-				m_type = RECENT;
-			}
-			else if (parser.checkWithArg <special_atom>(line, &pos, "uidnext", true))
-			{
-				m_type = UIDNEXT;
-			}
-			else if (parser.checkWithArg <special_atom>(line, &pos, "uidvalidity", true))
+			// "HIGHESTMODSEQ" SP mod-sequence-valzer
+			if (parser.checkWithArg <special_atom>(line, &pos, "highestmodseq", true))
 			{
-				m_type = UIDVALIDITY;
+				m_type = HIGHESTMODSEQ;
+
+				parser.check <SPACE>(line, &pos);
+				m_value = parser.get <IMAPParser::mod_sequence_value>(line, &pos);
 			}
 			else
 			{
-				parser.checkWithArg <special_atom>(line, &pos, "unseen");
-				m_type = UNSEEN;
-			}
+				if (parser.checkWithArg <special_atom>(line, &pos, "messages", true))
+				{
+					m_type = MESSAGES;
+				}
+				else if (parser.checkWithArg <special_atom>(line, &pos, "recent", true))
+				{
+					m_type = RECENT;
+				}
+				else if (parser.checkWithArg <special_atom>(line, &pos, "uidnext", true))
+				{
+					m_type = UIDNEXT;
+				}
+				else if (parser.checkWithArg <special_atom>(line, &pos, "uidvalidity", true))
+				{
+					m_type = UIDVALIDITY;
+				}
+				else
+				{
+					parser.checkWithArg <special_atom>(line, &pos, "unseen");
+					m_type = UNSEEN;
+				}
 
-			parser.check <SPACE>(line, &pos);
-			m_value = parser.get <IMAPParser::number>(line, &pos);
+				parser.check <SPACE>(line, &pos);
+				m_value = parser.get <IMAPParser::number>(line, &pos);
+			}
 
 			*currentPos = pos;
 		}
@@ -2007,6 +1987,10 @@ public:
 
 		enum Type
 		{
+			// Extensions
+			HIGHESTMODSEQ,
+
+			// Standard IMAP
 			MESSAGES,
 			RECENT,
 			UIDNEXT,
@@ -2027,6 +2011,11 @@ public:
 		{
 			return dynamic_cast <IMAPParser::number *>(m_value);
 		}
+
+		const IMAPParser::mod_sequence_value* value_as_mod_sequence_value() const
+		{
+			return dynamic_cast <IMAPParser::mod_sequence_value *>(m_value);
+		}
 	};
 
 
@@ -3882,6 +3871,9 @@ public:
 	//                  "BODY" section ["<" number ">"] SPACE nstring /
 	//                  "UID" SPACE uniqueid
 	//
+	// IMAP Extension for Conditional STORE (RFC-4551):
+	//
+	//   msg_att_item      /= "MODSEQ" SP "(" mod_sequence_value ")"
 
 	class msg_att_item : public component
 	{
@@ -3890,7 +3882,7 @@ public:
 		msg_att_item()
 			: m_date_time(NULL), m_number(NULL), m_envelope(NULL),
 			  m_uniqueid(NULL), m_nstring(NULL), m_body(NULL), m_flag_list(NULL),
-			  m_section(NULL)
+			  m_section(NULL), m_mod_sequence_value(NULL)
 
 		{
 		}
@@ -3905,6 +3897,7 @@ public:
 			delete (m_body);
 			delete (m_flag_list);
  			delete (m_section);
+ 			delete m_mod_sequence_value;
 		}
 
 		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
@@ -4015,6 +4008,18 @@ public:
 					m_body = parser.get <IMAPParser::body>(line, &pos);
 				}
 			}
+			// "MODSEQ" SP "(" mod_sequence_value ")"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "modseq", true))
+			{
+				m_type = MODSEQ;
+
+				parser.check <SPACE>(line, &pos);
+				parser.check <one_char <'('> >(line, &pos);
+
+				m_mod_sequence_value = parser.get <IMAPParser::mod_sequence_value>(line, &pos);
+
+				parser.check <one_char <')'> >(line, &pos);
+			}
 			// "UID" SPACE uniqueid
 			else
 			{
@@ -4042,7 +4047,8 @@ public:
 			BODY,
 			BODY_SECTION,
 			BODY_STRUCTURE,
-			UID
+			UID,
+			MODSEQ
 		};
 
 	private:
@@ -4057,6 +4063,7 @@ public:
 		IMAPParser::xbody* m_body;
 		IMAPParser::flag_list* m_flag_list;
 		IMAPParser::section* m_section;
+		IMAPParser::mod_sequence_value* m_mod_sequence_value;
 
 	public:
 
@@ -4070,6 +4077,7 @@ public:
 		const IMAPParser::xbody* body() const { return (m_body); }
 		const IMAPParser::flag_list* flag_list() const { return (m_flag_list); }
 		const IMAPParser::section* section() const { return (m_section); }
+		const IMAPParser::mod_sequence_value* mod_sequence_value() { return m_mod_sequence_value; }
 	};
 
 
@@ -4189,6 +4197,307 @@ public:
 
 
 	//
+	// resp_text_code ::= "ALERT" / "PARSE" /
+	//                    capability-data /
+	//                    "PERMANENTFLAGS" SPACE "(" #(flag / "\*") ")" /
+	//                    "READ-ONLY" / "READ-WRITE" / "TRYCREATE" /
+	//                    "UIDVALIDITY" SPACE nz_number /
+	//                    "UNSEEN" SPACE nz_number /
+	//                    atom [SPACE 1*<any TEXT_CHAR except "]">]
+	//
+	// IMAP Extension for Conditional STORE (RFC-4551):
+	//
+	//   resp-text-code      =/ "HIGHESTMODSEQ" SP mod-sequence-value /
+	//                          "NOMODSEQ" /
+	//                          "MODIFIED" SP set
+
+	class resp_text_code : public component
+	{
+	public:
+
+		resp_text_code()
+			: m_nz_number(NULL), m_atom(NULL), m_flag_list(NULL),
+			  m_text(NULL), m_capability_data(NULL)
+		{
+		}
+
+		~resp_text_code()
+		{
+			delete (m_nz_number);
+			delete (m_atom);
+			delete (m_flag_list);
+			delete (m_text);
+			delete m_capability_data;
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("resp_text_code");
+
+			string::size_type pos = *currentPos;
+
+			// "ALERT"
+			if (parser.checkWithArg <special_atom>(line, &pos, "alert", true))
+			{
+				m_type = ALERT;
+			}
+			// "PARSE"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "parse", true))
+			{
+				m_type = PARSE;
+			}
+			// capability_data
+			else if ((m_capability_data = parser.get <IMAPParser::capability_data>(line, &pos, true)))
+			{
+				m_type = CAPABILITY;
+			}
+			// "PERMANENTFLAGS" SPACE flag_list
+			else if (parser.checkWithArg <special_atom>(line, &pos, "permanentflags", true))
+			{
+				m_type = PERMANENTFLAGS;
+
+				parser.check <SPACE>(line, &pos);
+
+				m_flag_list = parser.get <IMAPParser::flag_list>(line, &pos);
+			}
+			// "READ-ONLY"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "read-only", true))
+			{
+				m_type = READ_ONLY;
+			}
+			// "READ-WRITE"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "read-write", true))
+			{
+				m_type = READ_WRITE;
+			}
+			// "TRYCREATE"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "trycreate", true))
+			{
+				m_type = TRYCREATE;
+			}
+			// "UIDVALIDITY" SPACE nz_number
+			else if (parser.checkWithArg <special_atom>(line, &pos, "uidvalidity", true))
+			{
+				m_type = UIDVALIDITY;
+
+				parser.check <SPACE>(line, &pos);
+				m_nz_number = parser.get <IMAPParser::nz_number>(line, &pos);
+			}
+			// "UIDNEXT" SPACE nz_number
+			else if (parser.checkWithArg <special_atom>(line, &pos, "uidnext", true))
+			{
+				m_type = UIDNEXT;
+
+				parser.check <SPACE>(line, &pos);
+				m_nz_number = parser.get <IMAPParser::nz_number>(line, &pos);
+			}
+			// "UNSEEN" SPACE nz_number
+			else if (parser.checkWithArg <special_atom>(line, &pos, "unseen", true))
+			{
+				m_type = UNSEEN;
+
+				parser.check <SPACE>(line, &pos);
+				m_nz_number = parser.get <IMAPParser::nz_number>(line, &pos);
+			}
+			// "HIGHESTMODSEQ" SP mod-sequence-value
+			else if (parser.checkWithArg <special_atom>(line, &pos, "highestmodseq", true))
+			{
+				m_type = HIGHESTMODSEQ;
+
+				parser.check <SPACE>(line, &pos);
+				m_mod_sequence_value = parser.get <IMAPParser::mod_sequence_value>(line, &pos);
+			}
+			// "NOMODSEQ"
+			else if (parser.checkWithArg <special_atom>(line, &pos, "nomodseq", true))
+			{
+				m_type = NOMODSEQ;
+			}
+			// "MODIFIED" SP sequence-set
+			else if (parser.checkWithArg <special_atom>(line, &pos, "modified", true))
+			{
+				m_type = MODIFIED;
+
+				parser.check <SPACE>(line, &pos);
+
+				m_sequence_set = parser.get <IMAPParser::sequence_set>(line, &pos);
+			}
+			// atom [SPACE 1*<any TEXT_CHAR except "]">]
+			else
+			{
+				m_type = OTHER;
+
+				m_atom = parser.get <IMAPParser::atom>(line, &pos);
+
+				if (parser.check <SPACE>(line, &pos, true))
+					m_text = parser.get <text_except <']'> >(line, &pos);
+			}
+
+			*currentPos = pos;
+		}
+
+
+		enum Type
+		{
+			// Extensions
+			HIGHESTMODSEQ,
+			NOMODSEQ,
+			MODIFIED,
+
+			// Standard IMAP
+			ALERT,
+			PARSE,
+			CAPABILITY,
+			PERMANENTFLAGS,
+			READ_ONLY,
+			READ_WRITE,
+			TRYCREATE,
+			UIDVALIDITY,
+			UIDNEXT,
+			UNSEEN,
+			OTHER
+		};
+
+	private:
+
+		Type m_type;
+
+		IMAPParser::nz_number* m_nz_number;
+		IMAPParser::atom* m_atom;
+		IMAPParser::flag_list* m_flag_list;
+		IMAPParser::text* m_text;
+		IMAPParser::mod_sequence_value* m_mod_sequence_value;
+		IMAPParser::sequence_set* m_sequence_set;
+		IMAPParser::capability_data* m_capability_data;
+
+	public:
+
+		Type type() const { return (m_type); }
+
+		const IMAPParser::nz_number* nz_number() const { return (m_nz_number); }
+		const IMAPParser::atom* atom() const { return (m_atom); }
+		const IMAPParser::flag_list* flag_list() const { return (m_flag_list); }
+		const IMAPParser::text* text() const { return (m_text); }
+		const IMAPParser::mod_sequence_value* mod_sequence_value() const { return m_mod_sequence_value; }
+		const IMAPParser::sequence_set* sequence_set() const { return m_sequence_set; }
+		const IMAPParser::capability_data* capability_data() const { return m_capability_data; }
+	};
+
+
+	//
+	// resp_text ::= ["[" resp_text_code "]" SPACE] (text_mime2 / text)
+	//               ;; text SHOULD NOT begin with "[" or "="
+
+	class resp_text : public component
+	{
+	public:
+
+		resp_text()
+			: m_resp_text_code(NULL)
+		{
+		}
+
+		~resp_text()
+		{
+			delete (m_resp_text_code);
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("resp_text");
+
+			string::size_type pos = *currentPos;
+
+			if (parser.check <one_char <'['> >(line, &pos, true))
+			{
+				m_resp_text_code = parser.get <IMAPParser::resp_text_code>(line, &pos);
+
+				parser.check <one_char <']'> >(line, &pos);
+				parser.check <SPACE>(line, &pos, true);
+			}
+
+			text_mime2* text1 = parser.get <text_mime2>(line, &pos, true);
+
+			if (text1 != NULL)
+			{
+				m_text = text1->value();
+				delete (text1);
+			}
+			else
+			{
+				IMAPParser::text* text2 =
+					parser.get <IMAPParser::text>(line, &pos, true);
+
+				if (text2 != NULL)
+				{
+					m_text = text2->value();
+					delete (text2);
+				}
+				else
+				{
+					// Empty response text
+				}
+			}
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		IMAPParser::resp_text_code* m_resp_text_code;
+		string m_text;
+
+	public:
+
+		const IMAPParser::resp_text_code* resp_text_code() const { return (m_resp_text_code); }
+		const string& text() const { return (m_text); }
+	};
+
+
+	//
+	// continue_req   ::= "+" SPACE (resp_text / base64)
+	//
+
+	class continue_req : public component
+	{
+	public:
+
+		continue_req()
+			: m_resp_text(NULL)
+		{
+		}
+
+		~continue_req()
+		{
+			delete (m_resp_text);
+		}
+
+		void go(IMAPParser& parser, string& line, string::size_type* currentPos)
+		{
+			DEBUG_ENTER_COMPONENT("continue_req");
+
+			string::size_type pos = *currentPos;
+
+			parser.check <one_char <'+'> >(line, &pos);
+			parser.check <SPACE>(line, &pos);
+
+			m_resp_text = parser.get <IMAPParser::resp_text>(line, &pos);
+
+			parser.check <CRLF>(line, &pos);
+
+			*currentPos = pos;
+		}
+
+	private:
+
+		IMAPParser::resp_text* m_resp_text;
+
+	public:
+
+		const IMAPParser::resp_text* resp_text() const { return (m_resp_text); }
+	};
+
+
+	//
 	// resp_cond_state ::= ("OK" / "NO" / "BAD") SPACE resp_text
 	//                     ;; Status condition
 	//
diff --git a/vmime/net/imap/IMAPStore.hpp b/vmime/net/imap/IMAPStore.hpp
index 6a06fdc9..e6b27d8d 100644
--- a/vmime/net/imap/IMAPStore.hpp
+++ b/vmime/net/imap/IMAPStore.hpp
@@ -86,6 +86,7 @@ public:
 
 	bool isSecuredConnection() const;
 	ref <connectionInfos> getConnectionInfos() const;
+	ref <IMAPConnection> getConnection();
 
 protected:
 
diff --git a/vmime/net/imap/IMAPUtils.hpp b/vmime/net/imap/IMAPUtils.hpp
index aea02ef9..591db3f3 100644
--- a/vmime/net/imap/IMAPUtils.hpp
+++ b/vmime/net/imap/IMAPUtils.hpp
@@ -37,6 +37,7 @@
 #include "vmime/net/folder.hpp"
 #include "vmime/net/message.hpp"
 #include "vmime/net/imap/IMAPParser.hpp"
+#include "vmime/net/imap/IMAPConnection.hpp"
 
 #include "vmime/mailboxList.hpp"
 
@@ -104,19 +105,23 @@ public:
 
 	/** Construct a fetch request for the specified messages, designated by their sequence numbers.
 	  *
+	  * @param cnt connection
 	  * @param list list of message numbers
 	  * @param options fetch options
 	  * @return fetch request
 	  */
-	static const string buildFetchRequest(const std::vector <int>& list, const int options);
+	static const string buildFetchRequest
+		(ref <IMAPConnection> cnt, const std::vector <int>& list, const int options);
 
 	/** Construct a fetch request for the specified messages, designated by their UIDs.
 	  *
+	  * @param cnt connection
 	  * @param list list of message UIDs
 	  * @param options fetch options
 	  * @return fetch request
 	  */
-	static const string buildFetchRequest(const std::vector <message::uid>& list, const int options);
+	static const string buildFetchRequest
+		(ref <IMAPConnection> cnt, const std::vector <message::uid>& list, const int options);
 
 	/** Convert a parser-style address list to a mailbox list.
 	  *
@@ -130,7 +135,7 @@ public:
 	  * @param uid globally unique UID (as returned by makeGlobalUID(), for example)
 	  * @return message UID
 	  */
-	static unsigned int extractUIDFromGlobalUID(const message::uid& uid);
+	static vmime_uint32 extractUIDFromGlobalUID(const message::uid& uid);
 
 	/** Construct a globally unique UID from UID Validity and a message UID.
 	  *
@@ -138,12 +143,12 @@ public:
 	  * @param messageUID UID of the message
 	  * @return global UID
 	  */
-	static const message::uid makeGlobalUID(const unsigned int UIDValidity, const unsigned int messageUID);
+	static const message::uid makeGlobalUID(const vmime_uint32 UIDValidity, const vmime_uint32 messageUID);
 
 private:
 
 	static const string buildFetchRequestImpl
-		(const string& mode, const string& set, const int options);
+		(ref <IMAPConnection> cnt, const string& mode, const string& set, const int options);
 };
 
 
diff --git a/vmime/net/maildir/maildirFolder.hpp b/vmime/net/maildir/maildirFolder.hpp
index 8a418268..940fcaae 100644
--- a/vmime/net/maildir/maildirFolder.hpp
+++ b/vmime/net/maildir/maildirFolder.hpp
@@ -117,6 +117,7 @@ public:
 	void copyMessages(const folder::path& dest, const std::vector <int>& nums);
 
 	void status(int& count, int& unseen);
+	ref <folderStatus> getStatus();
 
 	void expunge();
 
diff --git a/vmime/net/maildir/maildirFolderStatus.hpp b/vmime/net/maildir/maildirFolderStatus.hpp
new file mode 100644
index 00000000..80018b14
--- /dev/null
+++ b/vmime/net/maildir/maildirFolderStatus.hpp
@@ -0,0 +1,70 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#ifndef VMIME_NET_MAILDIR_MAILDIRFOLDERSTATUS_HPP_INCLUDED
+#define VMIME_NET_MAILDIR_MAILDIRFOLDERSTATUS_HPP_INCLUDED
+
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_MAILDIR
+
+
+#include "vmime/net/folderStatus.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace maildir {
+
+
+/** Holds the status of a Maildir folder.
+  */
+
+class VMIME_EXPORT maildirFolderStatus : public folderStatus
+{
+public:
+
+	// Inherited from folderStatus
+	unsigned int getMessageCount() const;
+	unsigned int getUnseenCount() const;
+
+	void setMessageCount(const unsigned int count);
+	void setUnseenCount(const unsigned int unseen);
+
+private:
+
+	unsigned int m_count;
+	unsigned int m_unseen;
+};
+
+
+} // maildir
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_MAILDIR
+
+#endif // VMIME_NET_MAILDIR_MAILDIRFOLDERSTATUS_HPP_INCLUDED
diff --git a/vmime/net/maildir/maildirMessage.hpp b/vmime/net/maildir/maildirMessage.hpp
index 4efc2eed..de8c1751 100644
--- a/vmime/net/maildir/maildirMessage.hpp
+++ b/vmime/net/maildir/maildirMessage.hpp
@@ -62,7 +62,7 @@ public:
 
 	int getNumber() const;
 
-	const uid getUniqueId() const;
+	const uid getUID() const;
 
 	int getSize() const;
 
diff --git a/vmime/net/message.hpp b/vmime/net/message.hpp
index 288e08a2..3b94fbf3 100644
--- a/vmime/net/message.hpp
+++ b/vmime/net/message.hpp
@@ -204,11 +204,12 @@ public:
 	  */
 	virtual int getNumber() const = 0;
 
-	/** Return the unique identified of this message (must fetch before).
+	/** Return the unique identifier (UID) of this message in its
+	  * folder (must fetch before).
 	  *
 	  * @return UID of the message
 	  */
-	virtual const uid getUniqueId() const = 0;
+	virtual const uid getUID() const = 0;
 
 	/** Return the size of the message (must fetch before).
 	  *
diff --git a/vmime/net/pop3/POP3Folder.hpp b/vmime/net/pop3/POP3Folder.hpp
index 952b8580..8a97213c 100644
--- a/vmime/net/pop3/POP3Folder.hpp
+++ b/vmime/net/pop3/POP3Folder.hpp
@@ -114,6 +114,7 @@ public:
 	void copyMessages(const folder::path& dest, const std::vector <int>& nums);
 
 	void status(int& count, int& unseen);
+	ref <folderStatus> getStatus();
 
 	void expunge();
 
diff --git a/vmime/net/pop3/POP3FolderStatus.hpp b/vmime/net/pop3/POP3FolderStatus.hpp
new file mode 100644
index 00000000..3e5d15a1
--- /dev/null
+++ b/vmime/net/pop3/POP3FolderStatus.hpp
@@ -0,0 +1,70 @@
+//
+// VMime library (http://www.vmime.org)
+// Copyright (C) 2002-2013 Vincent Richard <[email protected]>
+//
+// This program is free software; you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 3 of
+// the License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, write to the Free Software Foundation, Inc.,
+// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Linking this library statically or dynamically with other modules is making
+// a combined work based on this library.  Thus, the terms and conditions of
+// the GNU General Public License cover the whole combination.
+//
+
+#ifndef VMIME_NET_POP3_POP3FOLDERSTATUS_HPP_INCLUDED
+#define VMIME_NET_POP3_POP3FOLDERSTATUS_HPP_INCLUDED
+
+
+#include "vmime/config.hpp"
+
+
+#if VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_POP3
+
+
+#include "vmime/net/folderStatus.hpp"
+
+
+namespace vmime {
+namespace net {
+namespace pop3 {
+
+
+/** Holds the status of a POP3 folder.
+  */
+
+class VMIME_EXPORT POP3FolderStatus : public folderStatus
+{
+public:
+
+	// Inherited from folderStatus
+	unsigned int getMessageCount() const;
+	unsigned int getUnseenCount() const;
+
+	void setMessageCount(const unsigned int count);
+	void setUnseenCount(const unsigned int unseen);
+
+private:
+
+	unsigned int m_count;
+	unsigned int m_unseen;
+};
+
+
+} // pop3
+} // net
+} // vmime
+
+
+#endif // VMIME_HAVE_MESSAGING_FEATURES && VMIME_HAVE_MESSAGING_PROTO_POP3
+
+#endif // VMIME_NET_POP3_POP3FOLDERSTATUS_HPP_INCLUDED
diff --git a/vmime/net/pop3/POP3Message.hpp b/vmime/net/pop3/POP3Message.hpp
index c415e8a7..31b26154 100644
--- a/vmime/net/pop3/POP3Message.hpp
+++ b/vmime/net/pop3/POP3Message.hpp
@@ -62,7 +62,7 @@ public:
 
 	int getNumber() const;
 
-	const uid getUniqueId() const;
+	const uid getUID() const;
 
 	int getSize() const;