Thanks to all the people who replied to my previous post on blog spam. It's obviously not new, and it seems MT users have been hit quite badly by this. I guess removing links from comments is the first, quick step, but some kind of URL filter for the comment module in pyblosxom would be handy. Has anyone hacked something similar?

Just an extension that lets you create a blacklist of URLs would be a start, as the spammer URLS are always the same. They do know about some anti-anti-spam techniques though, and for example write "online casino" as "online-casino", so to read links they should be rendered first.