[Mimedefang] Why are non-multipart .eml attachments bad?

[Shayne Hardesty]

   See the quarantine report below..  I mostly see this with those chain 
mails that have been forwarded 6000 times around the net.  The nature of 
my question is, why does mimedefang consider non-multipart .eml 
attachments bad?  Does it break RFCs?  Does it break some MUAs?  Is it a 
possible security threat for some MUAs?

   For the time being I'm only keeping a copy of the e-mail in 
quarantine and delivering the original..  I see probably 10 - 20 of 
these a day, and if I refused them my users would probably pitch a fit 
and/or demand an explanation as to why they are being rejected.

   In the report below I've masked the sender and recipient to protect 
the "innocent".

Thanks,
Shayne


-------- Original Message --------
Subject: MIMEDefang Quarantine Report
Date: Mon, 18 Nov 2002 11:54:16 -0600
From: MIMEDefang <postmaster at realtysouth.com>
To: Administrator <postmaster at realtysouth.com>

An e-mail message was quarantined in the directory
/var/spool/MIMEDefang/qdir-2002-11-18-11.54.16-001 on the mail server.

The sender was '<XXXXXXXX at realtysouth.com>'.

The relay machine was localhost.localdomain (127.0.0.1).

The entire message was quarantined in 
/var/spool/MIMEDefang/qdir-2002-11-18-11.54.16-001/ENTIRE_MESSAGE

Recipient: <XXXXXXXX at yahoo.com>

----------
Here are the message headers:
Received: (from nobody at localhost)	by apollo.realtysouth.com 
(8.12.6/8.12.6/Submit) id gAIHsFUP002382	for XXXXXXXX at yahoo.com; Mon, 18 
Nov 2002 11:54:15 -0600
X-Authentication-Warning: apollo.realtysouth.com: nobody set sender to 
XXXXXXXX at realtysouth.com using -f
Message-ID: <1037642055.3dd9294768fbd at apollo.realtysouth.com>
Date: Mon, 18 Nov 2002 11:54:15 -0600
To: <XXXXXXXX at yahoo.com>
From: XXXXXXXX at realtysouth.com
Subject: Fwd: Fw: [Fwd: Fwd: Fw: Story Hour With Uncle Bill]
MIME-Version: 1.0
Content-Type: multipart/mixed; 
boundary="-MOQ103764205569ab8c18b793912849f7d01a9af55fcf"
User-Agent: IMP/PHP IMAP webmail program

----------
Here are the warning details:

A non-multipart .eml attachment named nsmail-2.eml was found