I think he means a separate box-physically infront of the zimbra mta.
ie: Not turn off ClamAV, but it doesn't make his boss/whoever happy to just use ClamAV alone (at least that's how I interprit 'political' reasons)
Can this symantec product act as an MTA? (pass the traffic through it)
old crap:
iptables-that was compiled from a bunch of (old) threads by kevinH & marc -didn't actually test anything myself
-yup, I don't have any iptables script/iptables running on any of my builds, I did kinda wonder-but posted anyway
Newer/2006 threads:
Move SMTP To Different Port SMTP Submission Port