I finally have my new version of AutoBan ready (as I mentioned earlier I was working on). This version requires Movable Type 3.2 to work, but it works much better than previous versions. I am now running it on all of my weblogs and it is running well and being somewhat helpful. I think it’s worthwhile because it is really zero maintenance and has a noticeable effect (after a start up period) on the incoming spam floods. You still need good filters but it magnifies the effects of such fiters, plus automatically bans any IP address for which you mark comments as spam manually.
P.S. This post was a big help in getting the configuration panel working.