Antivirus

Hi,   What is the best antivirus solution for my mail server Cyrus/Postfix ?   Thanks a lot,   Sebastien.

LMTP said: 451 4.3.0 System I/O error

Hi,   I'm runing Cyrus Imapd and Postfix, and I have a error message :   Jan  9 07:05:00 mail postfix/lmtp[25297]: AFFCB272D42: to=[EMAIL PROTECTED], relay=public/lmtp[public/lmtp], delay=44688, status=deferred (host public/lmtp[public/lmtp] said: 451 4.3.0 System I/O error) mail:/var/spool