I’ll take a look and appreciate the plug-in URL. My main hesitation is that I’ve heard that Akismet doesn’t let site owners override its blacklists. For example, I think I’m on the blacklist (no idea why, I promise, I’m innocent), and so when I posted to one blog recently, the owner told me he couldn’t get my post up.

I must admit -I’m not really a fan of typekey, or at least blogs where I have to use it to post – that will usually stop me from commenting.
Kind of ironic that I am posting that line on a Type-key blog…
Anyways, have you thought about moving to Akismet for Movable Type? Akismet has had a 100% catch rate for me, no false positives yet, and is completely invisible to the visitors. It would save them all the hassle of getting a Typekey acount in order to post…
Here’s the URL for the plugin: http://akismet.com/blog/2006/04/for-mt/

I experience the same thing at my Blog which is powered by Movable Type. I have found several valid comments filter into the Junk Comments so I make it a point to try to skim through those every couple of days to see if MT pushed anything in their by mistake.