I have a client who gets a TON of spam to their public IP.
I have put a Linux box running exim and spamassassin in front of it, and a bunch of Outlook rules to move mail into the Junk Email folder when spamassassin thought it saw spam. This worked well enough.
Now I've migrated them to Exchange 2007, is there a better way to "enforce" these Outlook rules for everyone, at the server side?
(Spamassassin works by inserting headers into incoming email. Here's some details.)
EDIT: Title changed (as sensibly suggested) from "Spamassassin / exim in front of Exchange 2007"