The original message was received at Sun, 10 Feb 2008 19:40:22 -0800
from lb.z57.com [209.75.14.120]
----- The following addresses had permanent fatal errors -----
<2@A.COM>
(reason: 550 Host unknown)
----- Transcript of session follows -----
550 5.1.2 <2@A.COM>... Host unknown (Name server: a.com: host not found)