I wondered why the links in my comments wouldn't display right. I had something to do with the Click Counter plugin I'm using. It's documented that it won't work if you have tags with single quotes surrounding the URL in stead of double quotes.
I found out that when there is just a URL in a comment, that make_clickable will add a tag around it. Unfortunately this uses single quites for tags to URL's. Wouldn't it be wise to change this to double quotes?
I'm not sure if single quotes are even w3c compliant.