Fwiw, I've moved the DNSBL issue out of SA and put it 'in front' with Postfix's postscreen.
Instead of just *one* DNSBL, which is imo always a risk, I use multiple dnsbls, and weight them in scoring. In my experience, it works fantastically well. A great write up on the approach is here http://rob0.nodns4.us/postscreen.html OF course, that presumes Postfix. You might me able to do the same with other servers, or maybe don't have the option at all. Jason
