Ok, all jokes asside.
Look at the header of the message, there should be some identifiable information that you can use in order to set up a spam filter.
Even though it "appears" to be from your email address, the email server it came from, the email program it was sent from, etc should all be contained in the head.
You could also setup a rule that ONLY allows email from your address with specific information in the header
That would probably be the most effective way.
Here is an example of a message header
Microsoft Mail Internet Headers Version 2.0
Received: from nawelemreb01.nadsuswe.nads.navy.mil ([10.0.194.16]) by NAWELEMREX20VA.nadsuswe.nads.navy.mil with Microsoft SMTPSVC(5.0.2195.6713);
Thu, 5 Apr 2007 09:41:35 -0700
Received: from NAEANRFKEB09.nadsusea.nads.navy.mil ([10.16.20.174]) by nawelemreb01.nadsuswe.nads.navy.mil with Microsoft SMTPSVC(5.0.2195.6713);
Thu, 5 Apr 2007 09:41:35 -0700
Received: from NAEANRFKEG02.nadsusea.nads.navy.mil ([10.16.20.70]) by NAEANRFKEB09.nadsusea.nads.navy.mil with Microsoft SMTPSVC(5.0.2195.6713);
Thu, 5 Apr 2007 12:39:00 -0400
Received: from naeanrfkfw12.nmci.navy.mil ([10.16.41.10]) by NAEANRFKEG02.nadsusea.nads.navy.mil with Microsoft SMTPSVC(5.0.2195.6713);
Thu, 5 Apr 2007 12:38:59 -0400
Received: from [138.162.0.121] by naeanrfkfw12.nmci.navy.mil
via smtpd (for insidesmtp.navy.mil [10.16.20.70]) with ESMTP; Thu, 5 Apr 2007 16:21:15 +0000
Received: from aprimo-relay4.autodesk.com ([198.102.112.90])
by navynrfkio04.nmci.navy.mil with ESMTP; 05 Apr 2007 12:48:06 -0400
X-BrightmailFiltered: true
X-Brightmail-Tracker: AAAAAQAAA+k=
Received: from APRPRDAPP04.ads.autodesk.com (aprprdapp04.autodesk.com [144.111.34.44])
by aprimo-relay4.autodesk.com (8.13.0/8.12.6) with ESMTP id l35GcvXV025898
for <ron.brooks@navy.mil>; Thu, 5 Apr 2007 09:38:57 -0700 (PDT)
Received: from mail pickup service by APRPRDAPP04.ads.autodesk.com with Microsoft SMTPSVC;
Thu, 5 Apr 2007 09:38:49 -0700
Thread-Topic: Autodesk Tour: Experience the Possibilities
thread-index: Acd3oOM93aCJACdxQJeN597tWYsIoA==
Reply-To: "Autodesk" <aprimo.americas.replies@autodeskcommunications.com>
From: "Autodesk" <aprimo.americas.replies@autodeskcommunications.com>
Sender: <aprimo.americas.bounces@autodeskcommunications.com>
To: "RON BROOKS" <ron.brooks@navy.mil>
Subject: Autodesk Tour: Experience the Possibilities
Date: Thu, 5 Apr 2007 09:38:49 -0700
Message-ID: <2d0a5301c777a0$e33d3320$2c226f90@ads.autodesk.com>
MIME-Version: 1.0
Content-Type: multipart/alternative;
boundary="----=_NextPart_000_2D0A54_01C77766.36DE5B20"
X-Mailer: Microsoft CDO for Windows 2000
Content-Class: urn:content-classes:message
Importance: normal
Priority: normal
X-MimeOLE: Produced By Microsoft MimeOLE V6.00.3790.326
X-OriginalArrivalTime: 05 Apr 2007 16:38:49.0520 (UTC) FILETIME=[E34B8B00:01C777A0]
Return-Path:
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