diff --git a/src/mailbox.cpp b/src/mailbox.cpp
index 2f625216..f6df5165 100644
--- a/src/mailbox.cpp
+++ b/src/mailbox.cpp
@@ -415,7 +415,7 @@ void mailbox::generate(utility::outputStream& os, const string::size_type maxLin
 		bool newLine = true;
 
 		m_name.encodeAndFold(os, maxLineLength, pos, &pos,
-			forceEncode ? text::FORCE_ENCODING : 0);
+			text::QUOTE_IF_POSSIBLE | (forceEncode ? text::FORCE_ENCODING : 0));
 
 		if (pos + m_email.length() + 3 > maxLineLength)
 		{
diff --git a/src/word.cpp b/src/word.cpp
index ce5ddfcc..ea8244a5 100644
--- a/src/word.cpp
+++ b/src/word.cpp
@@ -352,10 +352,22 @@ void word::generate(utility::outputStream& os, const string::size_type maxLineLe
 		noEncoding = false;
 	}
 
-	if (noEncoding)
+	// If possible and requested (with flag), quote the buffer (no folding is performed).
+	// Quoting is possible if and only if:
+	//  - the whole buffer is ASCII-only
+	//  - the buffer does not contain quoting character (")
+	//  - there is enough remaining space on the current line to hold the whole buffer
+	if ((flags & text::QUOTE_IF_POSSIBLE) &&
+	    asciiCount == m_buffer.length() &&
+	    m_buffer.find('"') == string::npos &&
+	    (curLineLength + 2 /* 2 x " */ + m_buffer.length()) < maxLineLength)
+	{
+		os << '"' << m_buffer << '"';
+		curLineLength += 2 + m_buffer.length();
+	}
+	// We will fold lines without encoding them.
+	else if (noEncoding)
 	{
-		// We will fold lines without encoding them.
-
 		string::const_iterator lastWSpos = m_buffer.end(); // last white-space position
 		string::const_iterator curLineStart = m_buffer.begin(); // current line start
 
diff --git a/vmime/text.hpp b/vmime/text.hpp
index dd4534d8..9760c48a 100644
--- a/vmime/text.hpp
+++ b/vmime/text.hpp
@@ -197,7 +197,8 @@ public:
 
 		FORCE_NO_ENCODING = (1 << 0),    /**< Just fold lines, don't encode them. */
 		FORCE_ENCODING = (1 << 1),       /**< Encode lines even if they are plain ASCII text. */
-		NO_NEW_LINE_SEQUENCE = (1 << 2)  /**< Use CRLF instead of new-line sequence (CRLF + TAB). */
+		NO_NEW_LINE_SEQUENCE = (1 << 2), /**< Use CRLF instead of new-line sequence (CRLF + TAB). */
+		QUOTE_IF_POSSIBLE = (1 << 3)     /**< Use quoting instead of encoding when possible (even if FORCE_ENCODING is specified). */
 	};
 
 	/** Encode and fold text in respect to RFC-2047.