Subject: Returned mail: see transcript for details

From: Mail Delivery Subsystem <[email-masked]>
Date: Fri, 24 Oct 2008 00:33:47 +0400 (MSD)

The original message was received at Fri, 24 Oct 2008 00:33:42 +0400 (MSD)
from [41.251.9.146]

   ----- The following addresses had permanent fatal errors -----
<[email-masked]>
    (reason: 550 5.7.1 Requested action not taken: mailbox not available)

   ----- Transcript of session follows -----
... while talking to local.rosneft.ru.:
>>> DATA
<<< 550 5.7.1 Requested action not taken: mailbox not available
550 5.1.1 <[email-masked]>... User unknown
<<< 503 5.5.2 Need Rcpt command.