you to re-send them using MIME.
+WARNING: Some mailers like Mozilla send your messages with
+---- message header ----
+Content-Type: text/plain; charset=us-ascii; format=flowed
+---- message header ----
+The problem is that "format=flowed" makes some of the mailers
+on receiving side to replace TABs with spaces and do similar
+changes. Thus the patches from you can look corrupted.
+
+To fix this just make your mozilla defaults/pref/mailnews.js file to look like:
+pref("mailnews.send_plaintext_flowed", false); // RFC 2646=======
+pref("mailnews.display.disable_format_flowed_support", true);
+
+
7) E-mail size.