This is strange. Using Wp 2.0.1, Spam Karma2.1 and the K2 template. Everything updated and clean.
When I submit a comment, the one which appears just after is a spam comment (to another post!!). Yet though my comment doesn't show immediately, it appears later. It's happend now for the past few days.
I only have SK2 running. I have other spam filters installed, such as Referer Bouncer, Tar Pit and WP spam assissin. But I have heard that SK2 is all you need for WP.
I'll try activating those other programs and see if it clears up.
But if anyone has any idea what I'm talking about, and you found a solution, please let me know.