[GPGrelay-Talk] Duplication of Subject: header

[Thomas H. <gpg...@ml...>]

Hi,

I have discovered a rather strange problem with my installation of
gpgrelay 0.959.

Some recipients were complaining that they got mails with a duplicate
Subject: header, like that:
| Received: from thorondor.akallabeth.de [127.0.0.1]
| 	by thorondor.akallabeth.de (10.0.1.201) 
| 	with SMTP (Classic Hamster Vr. 2.1 Build 2.1.0.11) ; Sat, 22 May 2010 23:39:25 +0200
| From: Thomas Hochstein <th...@in...>
| To: tes...@th...
! Subject: Test 3d - "Dies ist ein laengerer Test."
| Date: Sat, 22 May 2010 23:39:24 +0200
| Message-ID: <coj...@gw...>
| X-Mailer: Forte Agent 2.0/32.652
| MIME-Version: 1.0
| Content-Type: text/plain; charset=us-ascii
| Content-Transfer-Encoding: 7bit
! subject: 
| X-Relayed-By: GPGrelay Version 0.959 (Win32)
| Return-Path: <th...@in...>

Something has added another - empty - header "subject:".

A bit of debugging revealed that this only happens if the Subject:
contains (a) a German umlaut (or another 8bit character) and (b)
double quotes, and that the "something" adding another "subject:"
header is indeed gpgrelay. gpgrelay seems to believe the real Subject:
header to be empty, as it doesn't trigger on "Sign" in the Subject:
header and it logs an empty Subject: header, too.

I send my mails from Forté Agent 2.0 (a client) via gpgrelay to
Classic Hamster 2.1.0.11 (a local server); after processing through
gpgrelay, Hamster will do some rather substantial reprocessing of the
contents of some headers.

Further debugging - deactivating all header rewriting capabilities of
that local server - uncovered two other things:

(1) The kind of Subject: that gpgrelay can't handle really looks like
that (before it is reformatted by Hamster after processing through
gpgrelay):
| Subject: =?ISO-8859-1?Q?Test_3d_-_"Dies_ist?=
|  =?ISO-8859-1?Q?_ein_l=E4ngerer_Test.?=
|  =?ISO-8859-1?Q?"?=

(2) If I don't use double quotes in the Subject:, gpgrelay seems to
completely remove the MIME encoding from the Subject: header.

(a) Mail send through gpgrelay:
| From: Thomas Hochstein <th...@in...>
| To: tes...@th...
| Subject: Mäh? Mäh? Mäh? Mäh? Mäh? Mäh? Mäh? Mäh?
| Date: Sat, 22 May 2010 23:54:30 +0200
| X-Relayed-By: GPGrelay Version 0.959 (Win32)

(b) The same mail resend, but *not* send through gpgrelay:
| From: Thomas Hochstein <th...@in...>
| To: tes...@th...
| Subject: =?ISO-8859-1?Q?M=E4h=3F_M=E4h=3F_M=E4h=3F_M=E4h=3F?=
|  =?ISO-8859-1?Q?_M=E4h=3F_M=E4h=3F_M=E4h=3F_M=E4h?=
|  =?ISO-8859-1?Q?=3F?=
| Date: Sat, 22 May 2010 23:55:55 +0200

Perhaps gpgrelay can't handly quoted-printable MIME encoding
correctly? I don't think it should strip it, sending unencoded 8bit
characters in the Subject: header, and it certainly shouldn't stumble
on MIME enconding continuing over more than one line.

Perhaps someone could shed some light on this?

Regards,
-thh