Forward = Spoofing?

[HSorgYves]

Here is the RAW mail when sent through a mailinglist:

Code:

Return-Path: <mailing-bounces@glcr.lu>
Received: from mail.hosting-skills.org (castor.hosting-skills.org [195.24.76.190])
    by inmx1.pt.lu  with ESMTP id m8NANQDR010302;
    Tue, 23 Sep 2008 12:23:26 +0200
Received: from main.hosting-skills.org (localhost [127.0.0.1])
    by mail.hosting-skills.org (Postfix) with ESMTP id 31CAB2912C;
    Tue, 23 Sep 2008 12:23:26 +0200 (CEST)
X-Original-To: mailing@glcr.lu
Delivered-To: glcr.lu=mailing@localhost
X-policyd-weight: using cached result; rate: -1.5
Received: from smtpout1.pt.lu (mailsvr.pt.lu [194.154.192.108])
    (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
    (No client certificate requested)
    by mail.hosting-skills.org (Postfix) with ESMTP id F2CD76A027
    for <mailing@glcr.lu>; Tue, 23 Sep 2008 12:23:17 +0200 (CEST)
Received: from EMACS-Kreis.lan (ip-83-99-43-189.dyn.luxdsl.pt.lu
    [83.99.43.189]) by smtpout1.pt.lu  with ESMTP id m8NAMTQa009788
    for <mailing@glcr.lu>; Tue, 23 Sep 2008 12:23:16 +0200
Message-Id: <7061C94A-0314-4746-B8BB-595B359E5158@pt.lu>
From: Georges Kreis <georges.kreis@pt.lu>
To: mailing@glcr.lu
Content-Type: text/plain; charset=US-ASCII; format=flowed
Content-Transfer-Encoding: 7bit
Mime-Version: 1.0 (Apple Message framework v929.2)
Date: Tue, 23 Sep 2008 12:23:17 +0200
X-Mailer: Apple Mail (2.929.2)
Subject: [GLCR] Test
X-BeenThere: mailing@glcr.lu
X-Mailman-Version: 2.1.10
Precedence: list
List-Id: GLCR Announce List <mailing.glcr.lu>
List-Unsubscribe: <http://lists.hosting-skills.org/options/mailing@glcr.lu>,
    <mailto:mailing-request@glcr.lu?subject=unsubscribe>
List-Archive: <http://lists.hosting-skills.org/pipermail/mailing@glcr.lu>
List-Post: <mailto:mailing@glcr.lu>
List-Help: <mailto:mailing-request@glcr.lu?subject=help>
List-Subscribe: <http://lists.hosting-skills.org/listinfo/mailing@glcr.lu>,
    <mailto:mailing-request@glcr.lu?subject=subscribe>
Sender: mailing-bounces@glcr.lu
Errors-To: mailing-bounces@glcr.lu

Test

Why does this mail get accepted while the forward one does not?