+Unfortunately, at the time of this writing, these updates are provided far too slowly to adequately cope with the contemporary appearance rate of new mail worms, of which new mutations sometimes follow each other within hours. In the days it takes for the [ClamAV] signatures to be updated, your systems will be unprotected. The better competitors manage to have updates available often within hours of a new mutation's spotting -- of course, these are commercial offerings and don't have to rely on volunteers to sustain the infrastructure required from such response times.  

+  

+ [ClamAV] can be used by [ContentScanner]s to scan [Email]s on many [MTA]s. The [ClamAV] package includes one written by Nigel Horne for SendMail called __clamav-milter__. Another one is [smtp-vilter | http://www.etc.msys.ch/software/smtp-vilter/]. They both use the SendMail "milter" [API]. You can also use [ClamAV] to scan all [POP3] traffic with __pop3vscan__. See ClamAvPopVscan. In fact you can even use [ClamAV] to scan your incoming mail in Outlook: just get [ClamWin | http://clamwin.sf .net] and install the Outlook Plugin!