is this spam?

[edgardg]

I am getting lots (well, 4 or 5 a week) of these emails and usually with the subject:
**Message you sent blocked by our bulk email filter**

for these header I don't think I can tell if is legit or not, but it does look like it comes from one of our members.
But this is not the only one of our member we are receiving this from

Microsoft Mail Internet Headers Version 2.0
Received: from avspam.xxxx.xx.xx ([207.105.xx.x]) by mail.mydomain.com with Microsoft SMTPSVC(6.0.3790.3959);
	 Tue, 14 Aug 2007 08:28:03 -0700
MIME-Version: 1.0
From: My client email - Email Spam-Filter Center <postmaster@xxx.xx.xx>
Message-Id: <D002C245C7CA6B4E98BC5AD1D7DA14781CE950@myserver.mydomain.local>
Subject: **Message you sent blocked by our bulk email filter**
Content-Type: multipart/report; report-type=delivery-status;
    charset=utf-8;
    boundary="----------=_1187105103-24200-79"
To: <myUser@mydomain.com>
Date: Tue, 14 Aug 2007 08:25:03 -0700 (PDT)
Return-Path: <>
X-OriginalArrivalTime: 14 Aug 2007 15:28:03.0171 (UTC) FILETIME=[B4635B30:01C7DE87]

------------=_1187105103-24200-79
Content-Type: text/plain; charset="utf-8"
Content-Disposition: inline
Content-Transfer-Encoding: base64

------------=_1187105103-24200-79
Content-Type: message/delivery-status
Content-Disposition: inline
Content-Transfer-Encoding: 7bit
Content-Description: Delivery error report

------------=_1187105103-24200-79
Content-Type: text/rfc822-headers
Content-Disposition: inline
Content-Transfer-Encoding: 7bit
Content-Description: Undelivered-message headers

------------=_1187105103-24200-79--