I have a very weird problem I just noticed. For one commentor (and only one), WP is putting in a blank url link. This comment author does not supply a url, only email, but on all of his comments, WP inserts a url link. I've checked the database to make sure there is nothing stored in the commen_author_url field and there isn't.
You can view all the comments made by this comment author at this link http://mtdewvirus.com/authors/Jere/
Simply click on one of the post titles to see what I mean. When you see his comments, his name is linked to http:///
I am verrry confused! :-?