Returned mail: Data format error

[Post Office]

The original message was received at Wed, 18 Jul 2007 18:41:03 +0900
from linux.cz [170.86.76.90]

----- The following addresses had permanent fatal errors -----
sendmail na linux.cz

----- Transcript of the session follows -----
... while talking to mail server linux.cz.:
>>> MAIL FROM:"Post Office" <postmaster na linux.cz>
<<< 500 Refused

------------- další část ---------------
Dangerous Attachment has been Removed.  The file "instruction.zip" has been removed because of a virus.  It was infected with the "W32/MyDoom.BE na mm" virus.  File quarantined as: "". http://www.fortinet.com/VirusEncyclopedia/search/encyclopediaSearch.do?method=quickSearchDirectly&virusName=W32%2FMyDoom.BE%40mm