I see that. I am not sure what the CommentLink function is supposed to be doing - I didn't know it existed.
I see that ice is the only one that is using it. Can you please report this to bugs.lifetype.net, so someone can fix it? I think the fix is simply to remove that function call from the post.template.
Hrm - I see the postReplyCommentLink in postandcomments.template - that is more useful, so you'll want to check to see if that also causes an error.
Maybe the point of the CommentLink is so you could have comments on a separate page, like some blogs do, rather than having the comment form on the same page as the article text. I personally think that is annoying, but probably some people like it that way.