WE filter in the MTA (a milter) to spam assassin. Scores > 15 get dumped (highest false pos was 9.something in the 2 month pilot). We'll likely move that score to 10. Score > 5.0 gets MARKED (and the mail system moves it into a "quarantine" folder where 99% is spam but the occasional real messages makes it if really badly composed. Almost always some kind of bulk mail - lists, stuff with lots of HTML with wierd headers (bad message-ids, etc).
The number of "real mail" that marks false positive is pretty small. Damn close to zero for folks using plain text (old tyme unix folks). Milter catches mail during SMTP so we don't have to bounce stuff either. 60% of mail is spam here. Lopping off 1/3 of all mail and marking another 1/3rd is a win. (I'm tempted to turn it off 1 day a month to remind people). Quoting Ken Anderson ([EMAIL PROTECTED]): > We use MailScanner/SA with sendmail and limited per user rules. > It works good, but users are not so bright, and as you suggest, there's > no cure for that problem. > Ken > > > Daniel Senie wrote: > > >At 11:30 AM 9/15/2003, Ken Anderson wrote: > > > >>There's a proxy server that supports pop3 called prometo on > >>sourceforge that recently added SA support. I've tested it with > >>qpopper, and it works good with SA, but there's no way to do per user > >>rules. Pretty cool to do this on the pop3 side tho. > >> > >>Normally, SA is installed as a milter in sendmail or with another MTA. > > > > > >We use procmail to deliver to users' mailboxes, and run spamassassin > >from there. As a result, we can enable/disable on a per user basis. > >Allowing users control is still an issue, though. > > > >
