I ended up moving away from greylisting/sqlgrey in favor of Postscreen. The increasingly long delays in email, especially from email juggernauts like Gmail, wer

I ended up moving away from greylisting/sqlgrey in favor of Postscreen. The increasingly long delays in email, especially from email juggernauts like Gmail, were becoming a huge issue for users. Way too many complaints. Spambots used to be thwarted by greylisting but many of them are now more RFC compliant and will simply retry later. So far Postscreen has been doing an excellent job of reducing spam, and a fine tuned Spamassassin install has been catching the rest with no problems with false positives.