Date: Fri, 13 Dec 2013 01:07:54 +0100
From: Mail Delivery System <mailer-daemon@kundenserver.de>
To: mailman-users-bounces+user=example.com@python.org
Subject: Warning: message delayed 2 days
Message-Id: <0LkyaB-1VJZRH2iiz-00ahag@moeu2.kundenserver.de>

This message was created automatically by mail delivery software.

A message that you sent has not yet been delivered to one or more of
its recipients after 2 days.

The message has not yet been delivered to the following addresses:

  <user@example.com>

host lsvk.de[213.165.78.137]:
connection to mail exchanger failed

No action is required on your part. Delivery attempts will continue for
some time, and this warning may be repeated at intervals if the message
remains undelivered. Eventually the mail delivery software will give up,
and when that happens, the message will be returned to you.

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