got an empty email from root

[Ovidiu]

this morning I found the following email from root:

Return-Path: <root@h1550830.stratoserver.net>
Received: from localhost (localhost [127.0.0.1])
     by h1550830.stratoserver.net (Postfix) with ESMTP id 8F8182E6021F
     for <postmaster@web-designerz.de>; Wed, 6 May 2009 07:00:02 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at h1550830.stratoserver.net
X-Amavis-Alert: BAD HEADER SECTION, MIME error: error: unexpected end of
     header
X-Spam-Flag: NO
X-Spam-Score: 3.644
X-Spam-Level: ***
X-Spam-Status: No, score=3.644 tagged_above=3 required=4 tests=[AWL=-3.646,
     EMPTY_MESSAGE=0.607, MISSING_HB_SEP=2.5, MISSING_SUBJECT=1.285,
     NO_RELAYS=-0.001, TVD_SPACE_RATIO=2.899]
Received: from h1550830.stratoserver.net ([127.0.0.1])
     by localhost (h1550830.stratoserver.net [127.0.0.1]) (amavisd-new, port 10024)
     with ESMTP id f33Oj3Pfox1Z for <postmaster@web-designerz.de>;
     Wed, 6 May 2009 07:00:02 +0200 (CEST)
Received: by h1550830.stratoserver.net (Postfix, from userid 0)
     id F3CF92E60229; Wed, 6 May 2009 07:00:01 +0200 (CEST)
Message-Id: <20090506050001.F3CF92E60229@h1550830.stratoserver.net>
Date: Wed, 6 May 2009 07:00:01 +0200 (CEST)
From: root@h1550830.stratoserver.net (root)
To: undisclosed-recipients:;
Subject: [spam]

I'll look at my cron jobs and see if anything should run at 7am otherwise, will check mail log. Any other hints what this could be?