Regarding the RBL checks, we just didn't want the overhead (we process a ton of email). Also, we're a university and some of our "customer base" is pretty against the RBL concept.
Same thing with razor and pyzor.
Maybe those are what would get us more reasonable scores, I don't know. But for better or worse, using any of them would be a difficult sell at this point.
Ah, but the difference in this case is that SpamAssassin doesn't use these tests the same way your "customer base" is likely expecting. SpamAssassin queries DNSBLs and other external sources like Razor, Pyzor, and DCC, but does not consider a single positive result to be damning--it merely adds to the mail's score, just like every other test. In effect, these external tests are just treated as another form of evidence as SpamAssassin assembles its case against suspicious mail. This allows the mail to be analyzed more thoroughly, resulting in fewer false positives and false negatives, at the expense of a little more processing time and bandwidth.
The folks that oppose the use of DNSBLs and such are usually against the idea of blocking mail outright, based on someone else's recommendation. With SpamAssassin you can assign different scores to each DNSBL, so that if you trust one of them more than another, you can adjust their scores individually. If a particular DNSBL seems too triggerhappy for you, or has questionable listing policies, you can disable it entirely (by assigning it a score of 0), or just downgrade its weight with a lower score.
Robert LeBlanc <[EMAIL PROTECTED]>
Renaissoft, Inc.
Maia Mailguard <http://www.renaissoft.com/maia/>
