Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Wed, 15 Oct 2008 05:11:06 +0400 (MSD)

The original message was received at Wed, 15 Oct 2008 05:10:59 +0400 (MSD)
from corporat190-024196138.sta.etb.net.co [190.24.196.138] (may be forged)

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 5.1.1 <[email-masked]>... User unknown)

   ----- Transcript of session follows -----
... while talking to [10.0.1.2]:
>>> DATA
<<< 550 5.1.1 <[email-masked]>... User unknown
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.0.0 Need RCPT (recipient)