Error with mail replacing attachments

amended.eml

Received: from [192.168.1.200] (helo=blah) by accept with esmtp (Exim 4.72) (envelope-from <user@test.com>) id 1T4QaS-0000tn-F2 for user@test2.com; Thu, 23 Aug 2012 07:08:12 +0100
Date: Thu, 30 Aug 2012 15:38:54 +0100
From: user@test.com
To: user@test2.com
Message-ID: <004001cd86bd$313043c0$9390cb40$@test.com>
Subject: test3
Mime-Version: 1.0
Content-Type: multipart/mixed;
 boundary="----=_NextPart_000_0041_01CD86C5.92F54800";
 charset=UTF-8
Content-Transfer-Encoding: 7bit
X-Mailer: Microsoft Outlook 14.0
Thread-Index: Ac2GvR81BYetKvAXQkSS3cY6yxodQA==
Content-Language: en-gb



--
Date: Tue, 04 Sep 2012 15:00:01 +0100
Mime-Version: 1.0
Content-Type: image/png;
 charset=UTF-8;
 filename=logo.png
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
 filename=logo.png
Content-ID: <50460961608d5_73543fa4107b29bc82029@gts.mail>

iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAANMElEQVRo3u2a

original.eml

Received: from [192.168.1.200] (helo=blah)
	by accept with esmtp (Exim 4.72)
	(envelope-from <user@test.com>)
	id 1T4QaS-0000tn-F2
	for user@test2.com; Thu, 23 Aug 2012 07:08:12 +0100
From: <user@test.com>
To: <user@test2.com>
Subject: test3
Date: Thu, 30 Aug 2012 15:38:54 +0100
Message-ID: <004001cd86bd$313043c0$9390cb40$@test.com>
MIME-Version: 1.0
Content-Type: multipart/mixed;
	boundary="----=_NextPart_000_0041_01CD86C5.92F54800"
X-Mailer: Microsoft Outlook 14.0
Thread-Index: Ac2GvR81BYetKvAXQkSS3cY6yxodQA==
Content-Language: en-gb
X-tfe-messageid=1T4QaS-0000tn-F2

This is a multipart message in MIME format.

------=_NextPart_000_0041_01CD86C5.92F54800
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit

One attachments - should work

------=_NextPart_000_0041_01CD86C5.92F54800
Content-Type: image/png;
	name="logo.png"
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
	filename="logo.png"

iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAAACXBIWXMAAAsTAAALEwEAmpwYAAAK