I‘m pleased to announce that CommentCentral is compatible with WordPress 2.3.
Updates for WordPress can be downloaded from the regular site(s). I noticed that the tar-file got corrupted, so you may wish to go for the zip file (I noticed that the tar file is around 3 Meg while the zip file itself was only 1.5 Meg: they must have [had?] issues1).
And upgraded to 2.3.
1 See also the forum.