diff --git a/src/messageId.cpp b/src/messageId.cpp
index 407c859a..f749148c 100644
--- a/src/messageId.cpp
+++ b/src/messageId.cpp
@@ -101,6 +101,18 @@ void messageId::parse(const string& buffer, const string::size_type position,
 		}
 	}
 
+	// Fix for message ids without angle brackets (invalid)
+	bool hasBrackets = true;
+
+	if (p == pend)  // no opening angle bracket found
+	{
+		hasBrackets = false;
+		p = pstart;
+
+		while (p < pend && parserHelpers::isSpace(*p))
+			++p;
+	}
+
 	if (p < pend)
 	{
 		// Extract left part
@@ -119,7 +131,7 @@ void messageId::parse(const string& buffer, const string::size_type position,
 			// Extract right part
 			const string::size_type rightStart = position + (p - pstart);
 
-			while (p < pend && *p != '>') ++p;
+			while (p < pend && *p != '>' && (hasBrackets || !parserHelpers::isSpace(*p))) ++p;
 
 			m_right = string(buffer.begin() + rightStart,
 			                 buffer.begin() + position + (p - pstart));
diff --git a/tests/parser/messageIdTest.cpp b/tests/parser/messageIdTest.cpp
index a7a2a97c..6330f157 100644
--- a/tests/parser/messageIdTest.cpp
+++ b/tests/parser/messageIdTest.cpp
@@ -32,6 +32,7 @@ VMIME_TEST_SUITE_BEGIN
 
 	VMIME_TEST_LIST_BEGIN
 		VMIME_TEST(testParse)
+		VMIME_TEST(testParseInvalid)
 		VMIME_TEST(testGenerate)
 	VMIME_TEST_LIST_END
 
@@ -45,6 +46,15 @@ VMIME_TEST_SUITE_BEGIN
 		VASSERT_EQ("1.2", "b", m1.getRight());
 	}
 
+	void testParseInvalid()
+	{
+		vmime::messageId m1;
+		m1.parse("foo@bar");
+
+		VASSERT_EQ("1.1", "foo", m1.getLeft());
+		VASSERT_EQ("1.2", "bar", m1.getRight());
+	}
+
 	void testGenerate()
 	{
 		vmime::messageId m1;
diff --git a/vmime/net/imap/IMAPParser.hpp b/vmime/net/imap/IMAPParser.hpp
index da812952..c535e1aa 100644
--- a/vmime/net/imap/IMAPParser.hpp
+++ b/vmime/net/imap/IMAPParser.hpp
@@ -48,7 +48,7 @@
 #include <stdexcept>
 
 
-//#define DEBUG_RESPONSE 1
+#define DEBUG_RESPONSE 1
 
 
 #if DEBUG_RESPONSE