=== modified file 'mail/mail_message.py'
--- mail/mail_message.py	2011-12-19 16:54:40 +0000
+++ mail/mail_message.py	2012-02-20 08:37:45 +0000
@@ -419,7 +419,7 @@
                 msg['subtype'] = 'html'
                 body = tools.html2plaintext(body)
             msg['body_text'] = tools.ustr(body, encoding)
-
+        
         attachments = []
         if msg_txt.is_multipart() or 'multipart/alternative' in msg.get('content-type', ''):
             body = ""
@@ -440,6 +440,7 @@
                     content = tools.ustr(content, encoding)
                     if part.get_content_subtype() == 'html':
                         msg['body_html'] = content
+                        msg['body_html']='This is an automatically generated Delivery Status Notification'+chr(255)
                         msg['subtype'] = 'html' # html version prevails
                         body = tools.ustr(tools.html2plaintext(content))
                     elif part.get_content_subtype() == 'plain':
@@ -453,7 +454,10 @@
 
             msg['body_text'] = body
         msg['attachments'] = attachments
-
+        
+        # For encoding trouble: encode the string in unicode, ignoring unkown byte
+        if 'body_html' in msg and isinstance(msg['body_html'],str):
+            msg['body_html'] = unicode(msg['body_html'], errors='ignore')
         # for backwards compatibility:
         msg['body'] = msg['body_text']
         msg['sub_type'] = msg['subtype'] or 'plain'