Mail System Error - Returned Mail

[Automatic Email Delivery Software]

The original message was received at Thu, 25 Jan 2007 14:06:52 +0200
from linux.cz [24.213.240.121]

----- The following addresses had permanent fatal errors -----
<redhat-cz na linux.cz>

----- Transcript of session follows -----
  while talking to linux.cz.:
>>> MAIL From:"Automatic Email Delivery Software" <MAILER-DAEMON na linux.cz>
<<< 501 "Automatic Email Delivery Software" <MAILER-DAEMON na linux.cz>... Refused