[Mimedefang] high-load scanning with mimedefang

[Rudolph Pereira]

Hello,
I was wondering if anyone had suggestions on fast+efficient virus
scanners that could be used with mimedefang on highly-loaded servers.
I've looked at two classes of scanners - the per-mail cmdline scanners
and the daemonised ones that stay resident (I don't think there's any
others that would work with mimedefang?)
and was after recommendations about particular products.
The former class (cmdline) seem far too slow for busy mail servers (I've
measured something like 1/5th to 1/8th the throughput of
sendmail+mimedefang alone (given similar filter rules), while although the
latter are much faster, there seem to be
far fewer products that support a memory-resident daemon, and most of
them are expensive (given the amount of
traffic/domains/mailboxes/whatever I'm looking at)
I'm also wondering about what I should look at at getting better
performance out of mimedefang; my tests seem to indicate about a 20%
performance drop compared to plain sendmail. I've looked at the obvious
things like putting mimedefang's spool on tmpfs and staring at my filter
code for performance hogs, but are there any general suggestions that
peoeple have for this kind of thing?
Oh, most of my tests/work have been on a 2-cpu 
solaris 5.8/sparc machine with perl-5.005 and mimedefang 2.23 (though
I'm not tied to that platform/os) 
Any thoughts/information would be appreciated.

Thanx.