diff --git a/mozilla/mailnews/mailnews.js b/mozilla/mailnews/mailnews.js
index 2b6675a37d3..dd78d4ff998 100644
--- a/mozilla/mailnews/mailnews.js
+++ b/mozilla/mailnews/mailnews.js
@@ -398,3 +398,5 @@ pref("mailnews.max_header_display_length",3); // number of addresses to show
 pref("messenger.throbber.url","http://www.mozilla.org");
 pref("compose.throbber.url","http://www.mozilla.org");
 pref("addressbook.throbber.url","http://www.mozilla.org");
+
+pref("mailnews.send_plaintext_flowed", true); // RFC 2646=======
\ No newline at end of file
diff --git a/mozilla/modules/libpref/src/init/mailnews.js b/mozilla/modules/libpref/src/init/mailnews.js
index 2b6675a37d3..dd78d4ff998 100644
--- a/mozilla/modules/libpref/src/init/mailnews.js
+++ b/mozilla/modules/libpref/src/init/mailnews.js
@@ -398,3 +398,5 @@ pref("mailnews.max_header_display_length",3); // number of addresses to show
 pref("messenger.throbber.url","http://www.mozilla.org");
 pref("compose.throbber.url","http://www.mozilla.org");
 pref("addressbook.throbber.url","http://www.mozilla.org");
+
+pref("mailnews.send_plaintext_flowed", true); // RFC 2646=======
\ No newline at end of file