Splogs are driving me mad

I mentioned previously how blogs and forums (fora) are converging. I've been running the excellent VBSeo mod on a couple of forums for the last few months and the SEO results have been more than satisfactory, however there's no such thing as a free lunch :) The downside is that the forum is being hit with trackbacks from splogs all the time. In the last 24 hours it got really silly, with splogs hitting it every couple of minutes. I've had to disable trackbacks until I can come up with a sane solution for filtering them. Yes they do go into a moderation queue, but the number of them is such that moderating that queue could become a full time job!