I've been playing with two anti-spam plugins, from Kahuna Burger, and I think they're nearly ready for primetime.
The first is mt-proxyplug, which seems to be stopping a fair number of attempts right at the start. I needed to hack it a little bit, though, because I run a mod_perl proxy setup. This gets me a lot of speed, and keeps most things from hitting the heavy mod_perl apache on the backend. And with it under mod_perl 1, things actually work right. That is, things besides MT-Blacklist. While MT-Blacklist is an awesome program, it is rather... unsupported under mod_perl. Oh well.
The second plugin I'm using now is mt-spamassassin (the lower-case one, not to be confused with MT-SpamAssassin. The latter is very nice and full featured, however, I'm looking for simple, run it, and it's so simple it doesn't break when run under mod_perl. Maybe I want too much. I did use the rule sets from the second one, and added a few of my own.
The one I'm using is very simple, just slightly above proof of concept stage. I run SpamAssassin as a daemon on the same machine, and pass comments to that. The latter MT-SpamAssassin actually imports the SA perl module, which is probably a good way to go for a lot of things, but I want to keep my mod_perl processes a bit smaller than that. SpamAssassin imported into apache/mod_perl does not strike me as a small solution.
The good thing is, the latter heavy-weight plugin author has already gone through and made a rule set out of the MT-Blacklist rules, and that's what I'm using as a base. I added a few rules to that, and I think with a bit of keeping up on it, it'll work.
I still have to hack trackback support into these. It seems that trackbacks are the red-headed step-child in MT.
After I think this has been working reasonably for a little bit, and I'm not getting errors out of it, I'll deploy it on the Mises Institute blog.
Maybe time to write a simple script to go through the MT DB and see if anything would be moderated or blocked that shouldn't be... oh, and there is no message if it gets all-out denied.
So Spam me. Spam me hard. I want lots of attempted messages, and I want to know if legitimate comments get blocked.

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