PM notifications sent to a particular user are bouncing back with the following error. Any ideas how to correct this?

Code
The original message was received at Thu, 03 Aug 2006 08:50:58 -0500

  ----- The following addresses had permanent fatal errors -----
<[email protected]>

  ----- Transcript of session follows -----
... while talking to dallas.docucorp.com
>>> DATA
<<< 550 Requested action not taken: Nonstandard SMTP line terminator.

Reporting-MTA: DNS; newmail.grayloon.com
Arrival-Date: Thu, 03 Aug 2006 08:50:58 -0500

Original-Recipient: RFC822; <[email protected]>
Final-Recipient: RFC822; <[email protected]>
Action: failed
Remote-MTA: DNS; dallas.docucorp.com
Last-Attempt-Date: Thu, 03 Aug 2006 08:50:58 -0500

From: <[email protected]>
Reply-To: <[email protected]>
To: <[email protected]>
Subject: You have new messages

Message-Id: <[email protected]>
Date: Thu,  3 Aug 2006 08:50:58 -0500 (CDT)


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