Upgrade to 1.5, comments popup reloads index page!

Hi guys, I hope somebody has had the same problem. I just upgraded from 1.2 to 1.5 installed my own theme… everything seems to work fine, except for a few things.

The one that worries me the most right now is that, when I hit the submit button for a comment (I am using comments-popup.php) the page does not reload just the popup, but the whole index page with comments embedded.

It looks as if the post method of the comment form gets the wrong data… any ideas on how to solve that?

It used to work fine until I upgraded to 1.5.