[Mimedefang] Only scanning incoming messages?

[Rich West]

Just to second this opinion, I would like to point out that, by allowing 
outgoing email to remain unfiltered yet filter incoming, you are really 
only doing half of the job,  Viruses enter a clean environment through 
many other ways than email, and if a known virus originates from within 
your organization and spreads via email, it will flow freely.

Same goes for SPAM.

-Rich

>It is never a good idea to base processing decisions on the sender
>e-mail address, because that's easy to fake.  The relay IP address
>is a lot harder to fake, and practically impossible if you use
>proper ingress rules on your firewall.
>