The original message was received at Sun, 10 Feb 2008 18:25:16 -0800
from lb.z57.com [209.75.14.120]
----- The following addresses had permanent fatal errors -----
<a@aol.com>
(reason: 550 MAILBOX NOT FOUND)
----- Transcript of session follows -----
... while talking to mailin-01.mx.aol.com.:
>>> RCPT To:<a@aol.com>
<<< 550 MAILBOX NOT FOUND
550 5.1.1 <a@aol.com>... User unknown