Spammers are everywhere. Every day, a dozen spammers post a fake track-back to my site that links to some porn or Viagra site. Because they come in from a ton of different IP addresses, my blog software, Movable Type, can't filter them out. Worse yet, some spammers have even automated comment spam. It usually starts with something like, "Great blog entry; you've really got me thinking. Click here to get meds below market prices." I guess they figure that my approval system will only show me the first line and I'll allow the comment to be posted. Yikes.
Please email me or comment here if you have the same problem, or know of a solution. As far as I know, nobody has created spam filters for this. But clearly they are needed.