Not sure whether this goes under 3rd party addons, but then again...
I'm using Smoothwall as firewall at my company, and recently installed the mfilter mod, which is an implementation of the dspam mail filter. This also work in conjunction with ClamAV to filter out viruses/spam/porn/phishing mails at gateway/firewall level.
This is to do two things :
1. Create a proxy mail server which sits between the Exchange mail server and the outside world, and 2. Filters unwanted mail.
In both cases I was successful. Already, the majority of phishing mails is blocked, and it also blocks the majority of porn mails. It still is training to pick up blue pill advertisements, but already there is a huge improvement in that 84% of blue pills advertisements gets blocked.
As for false positives, I've had two or three false positives (due to a mistake on my part) but if you consider the fact that it have done over 8714 messages, it is very good.
I'm very impressed with this software so far.
Of course, I'm keeping the current installation of Symantec Mail Security and Symantec Antivirus on the server, to enable protection on the internal network.
Regards
Librarian
< Message edited by The_Librarian -- 30.May2006 9:49:35 AM >