(cc SAC for tricky spam problem)
OK, the header helps. The problem is now clear to me:
- 'grass-dev@lists.osgeo.org' was used as fake sender
- 'grass-dev@lists.osgeo.org' is an address in the list of non-member
addresses whose postings should be automatically accepted in Mailman
(don't remember why, possibly for the trac/gforge notifier?)
Hence such mails are accepted 
You are right that there is no spam filtering on osgeo.org which
might help to avoid such problems (on grass.itc.it it didn't happen
since bogofilter was in place).
Markus
On Dec 24, 2007 7:42 PM, Maris Nartiss <maris.gis@gmail.com> wrote:
Merry Christmas and sorry, You are wrong.
http://lists.osgeo.org/pipermail/grass-dev/2007-December/034590.html
Here is full message header:
Delivered-To: maris.gis@gmail.com
Received: by 10.143.166.3 with SMTP id t3cs659859wfo;
Fri, 21 Dec 2007 01:16:25 -0800 (PST)
Received: by 10.151.14.5 with SMTP id r5mr345770ybi.57.1198228581971;
Fri, 21 Dec 2007 01:16:21 -0800 (PST)
Return-Path: <grass-dev-bounces@lists.osgeo.org>
Received: from lists.osgeo.org (lists.osgeo.org [66.223.95.242])
by mx.google.com with ESMTP id 58si1165512rnw.4.2007.12.21.01.16.02;
Fri, 21 Dec 2007 01:16:21 -0800 (PST)
Received-SPF: pass (google.com: best guess record for domain of
grass-dev-bounces@lists.osgeo.org designates 66.223.95.242 as
permitted sender) client-ip=66.223.95.242;
Authentication-Results: mx.google.com; spf=pass (google.com: best
guess record for domain of grass-dev-bounces@lists.osgeo.org
designates 66.223.95.242 as permitted sender)
smtp.mail=grass-dev-bounces@lists.osgeo.org
Received: from osgeo1.osgeo.org (localhost.localdomain [127.0.0.1])
by lists.osgeo.org (Postfix) with ESMTP id 9AC02E040B1;
Fri, 21 Dec 2007 04:16:01 -0500 (EST)
X-Original-To: grass-dev@lists.osgeo.org
Delivered-To: grass-dev@lists.osgeo.org
Received: from director (unknown [83.239.180.102])
by lists.osgeo.org (Postfix) with SMTP id 2A7A7E01EEA
for <grass-dev@lists.osgeo.org>; Fri, 21 Dec 2007 04:15:56 -0500 (EST)
X-Originating-IP: [87.03.91.6]
X-Originating-Email: [grass-dev@lists.osgeo.org]
X-Sender: grass-dev@lists.osgeo.org
Received: (qmail 3068 by uid 295); Fri, 21 Dec 2007 12:15:53 +0300
Message-Id: <20071221151553.3070.qmail@director>
To: <grass-dev@lists.osgeo.org>
From: VIAGRA � Official Site <grass-dev@lists.osgeo.org>
MIME-Version: 1.0
Importance: High
Date: Fri, 21 Dec 2007 04:15:56 -0500 (EST)
Subject: [GRASS-dev] RE: SALE 70% OFF on Pfizer
X-BeenThere: grass-dev@lists.osgeo.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: GRASS GIS Development mailing list <grass-dev.lists.osgeo.org>
List-Unsubscribe: <http://lists.osgeo.org/mailman/listinfo/grass-dev>,
<mailto:grass-dev-request@lists.osgeo.org?subject=unsubscribe>
List-Archive: <http://lists.osgeo.org/pipermail/grass-dev>
List-Post: <mailto:grass-dev@lists.osgeo.org>
List-Help: <mailto:grass-dev-request@lists.osgeo.org?subject=help>
List-Subscribe: <http://lists.osgeo.org/mailman/listinfo/grass-dev>,
<mailto:grass-dev-request@lists.osgeo.org?subject=subscribe>
Content-Type: multipart/mixed; boundary="===============2096838104=="
Sender: grass-dev-bounces@lists.osgeo.org
Errors-To: grass-dev-bounces@lists.osgeo.org--===============2096838104==
Content-Type: text/html
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