There's lots of good options, you could install Perl on the exchange server and proxy smtp with assp, or setup a Linux based MTA and install assp on it or something like postfix/sqlgrey/spamassassin/clamav/amavisd-new that of which there are lots of how to's.
By far the easiest is assp and it does work well. jlc -----Original Message----- From: Daniel Hood [mailto:dsmh...@gmail.com] Sent: Tuesday, March 10, 2009 9:12 PM To: MS-Exchange Admin Issues Subject: Filtering Spam Hey, I'm looking for a good open-source/free product that we can use in conjuction with our exchange server to filter out spam. We did have mailwasher but due to the opensource version being crap and the enterprise version costing as much as putting an entire detriot high school through college, I'm looking for another free/open-source spam product that actually works. Ideas? Daniel ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~ ~ Ninja Email Security with Cloudmark Spam Engine Gets Image Spam ~ ~ http://www.sunbeltsoftware.com/Ninja ~