Word Press Spam Fighter Suddenly Failing

I have a brilliant spammer attacking me.

I added one of his domains from his e-mail adress to the blacklist, yet I get tons of comments with it to moderate. I even get a few that make it live on my site, without having a post previously approved!

What is going on? I suppose mostly I’m trying to alert the staff of flaws. But I’m also wondering if this is happening at other blogs.