Fix: wrong decoding of subjects (headers) not encoded like the python function 'decode_header' understands rfc2047. Added file u2u_decode.py which corrects this problem, taken from here: http://bugs.python.org/issue1079.

extensions/webmail/lib.py

@@ -16,7 +16,7 @@ from django.utils.translation import ugettext as _
 from django.conf import settings
 from modoboa.lib import decode, tables, imap_utf7, Singleton
 from modoboa.lib.email_listing import MBconnector, EmailListing, Email
-from modoboa.lib import tables, imap_utf7, parameters, static_url
+from modoboa.lib import tables, imap_utf7, parameters, static_url, u2u_decode
 
 
 class WMtable(tables.Table):
@@ -118,13 +118,7 @@ class IMAPheader(object):
 
     @staticmethod
     def parse_subject(value, **kwargs):
-        res = ""
-        dcd = decode_header(re.sub("[\\r\\n]+", "", value))
-        for part in dcd:
-            if res != "":
-                res += " "
-            res += part[0].strip(" ")
-        return decode(res)
+        return u2u_decode.u2u_decode(value)
 
 class ConnectionsManager(type):
     def __init__(cls, name, bases, dict):

lib/u2u_decode.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python
+# u2u_decode.py
+# unstructured rfc2047 header to unicode
+#
+import re
+from email.header import decode_header, make_header
+
+# check spaces between encoded_words (and strip them)
+sre = re.compile(r'\?=[ \t]+=\?')
+# re pat for MIME encoded_word (without trailing spaces)
+mre = re.compile(r'=\?[^?]*?\?[bq]\?[^? \t]*?\?=', re.I)
+
+def decode_mime(m):
+    # substitute matching encoded_word with unicode equiv.
+    h = decode_header(m.group(0))
+    u = unicode(make_header(h))
+    return u
+
+def u2u_decode(s):
+    # utility function for (final) decoding of mime header
+    # note: resulting string is in one line (no \n within)
+    # note2: spaces between enc_words are stripped (see RFC2047)
+    s = ''.join(s.splitlines())
+    s = sre.sub('?==?', s)
+    u = mre.sub(decode_mime, s)
+    return u
+
+if __name__ == '__main__':
+    import sys
+    if len(sys.argv) > 1:
+        s = sys.argv[1]
+    else:
+        s = """[Apache-Users 7784] ServerAlias =?ISO-2022-JP?B?GyRAGyRCJEsbKEI=?=:(
+ =?ISO-2022-JP?B?GyRCJTMlbSVzGyhC?=)=?ISO-2022-JP?B?GyRCJHI7SBsoQg==?=
+ =?ISO-2022-JP?B?GyRAGyRCTVEkOSRrJEg1c0YwJCwkKiQrJDckJBsoQg==?="""
+        s = 'Sm=?ISO-8859-1?B?9g==?=rg=?ISO-8859-1?B?5Q==?=sbord'
+    u = u2u_decode(s)
+    print u
+