Yesterday I backported a recent postfix version to woody, and installed it together with postgrey. Yay! I finally have greylisting on my mailserver.

This cut down the amount of spam by a lot. The server is now processing only 20% of its former incoming mail volume. Spam rejects dropped to about 2% of the former quantities, marked spam down to 50%.

Almost all spam I still see in my “likely spam” and Inbox folders is forwarded by other accounts such as my university account, an old freemail account (both of which do have a pretty good spam protection by now) and via my Debian address. Actually most spam I get now is addressed to my @d.o email.