you can policy route all outboud smtp traffic to a local mail handling
network which scans mail for that sort of thing.  we're going through
an overhaul on our mail clustering at work to add virus checking to
outbound mail to insure that we're not a source of virii going out to
customers.

more information regarding policy routing can be found here. [1]


outbound analysis of mail for virii on your outbound mailserver is an
exercise for you to handle. ;-)


when last we saw our hero (Wednesday, Nov 27, 2002), 
 Raymond Norton was madly tapping out:
> I manage a large network of school districts.  There is an ongoing
> problem of some of their mail servers sending out virus type
> traffic. Is there a solution I can put at our gateway that would
> stop virus type mail from being sent to the world? In theory it
> would be nice to add an access-list to our boarder router that would
> send all outgoing mail to a server to be scanned before leaving our
> network.
> 


references
----------

[1] - http://www.cisco.com/warp/public/cc/techno/protocol/tech/plicy_wp.htm
      http://www.cisco.com/en/US/tech/tk648/tk365/technologies_tech_note09186a008009481d.shtml

-- 
steve ulrich                       sulrich at botwerks.org
PGP: 8D0B 0EE9 E700 A6CF ABA7  AE5F 4FD4 07C9 133B FAFC