[Mimedefang] relay_by_domain, aliasing and SpamAssassin question

[Rajesh Bhandari]

Hi all,

Config: RedHat 7.3, Sendmail 8.12.5, MD 2.21, SA 2.41, TrendMicro
VirusWall.
All of this configured in a sendmail sandwich. 
Sendmail1->VirusWall->Sendmail2 (BTW, this is a recommended VirusWall
configuration).  Sendmail1 has the milter.  I use MD for attachment
blocking and SA.   Let me say that this works very well indeed.

The plan is to make this a mailhub/relay relaying mail for four
different internal sub-domains.  So I would do alias expansion to
deliver the mail to the final server.  The problem is that each internal
domain wants to use a different SA threshold and scores/rules. 

My plan had been to
- use relay_by_domain
- create separate sa-mimedefang-<domain>.cf files
- call spam_assassin_check ( sa-mimedefang-<domain>.cf)

However, in the message referenced below, David says that:
—-------------------
MD listens in on the SMTP dialog, and has no knowledge of
alias expansion.  There are (expensive) ways around this, but they are
probably not worth it.  
--------------------
http://lists.roaringpenguin.com/pipermail/mimedefang/2002-August/002065.html

Without alias expansion, the domain will remain user at domain.com instead
of being user at dom1.domain.com, user at dom2.domain.com etc.  And I want to
use dom1.domain.com to match the sa-mimedefang-<domain>.cf file so I can
do the different scores etc.

Thoughts, Comments, Solutions ?

I should mention that I have thought of splitting up the MD and SA
functionality as follows:
- Sendmail1-MD-Attachment blocking only
- Sendmail1 does alias expansion
- Sendmail 2 - MD - SA with different sa-md files.

This would involve running two copies of MD.  Can I do that?  Any other
ways of solving this problem?

Rajesh