=== modified file 'Mailman/MailList.py'
--- Mailman/MailList.py	2010-06-29 16:01:58 +0000
+++ Mailman/MailList.py	2010-11-18 17:57:37 +0000
@@ -1258,7 +1258,7 @@
                     except IndexError:
                         subpart = None
                     if subpart:
-                        s = StringIO(subpart.get_payload())
+                        s = StringIO(subpart.get_payload(decode=True))
                         while True:
                             line = s.readline()
                             if not line: