Wow... that is REALLY weird. I had something somewhat similar happen to me with Gmail a while back. Here's a screenshot of it:
http://bst82551.ath.cx:8181/pics/SS/wtf.jpg
Here is the URL to the thread in which I posted my problems:
http://kmeleonbrowser.org/forum/read.php?f=1&i=31652&t=31630
It was narrowed down to being something in the profile, but I don't think anyone ever completely figured out what it was. Try creating a new profile and see what that does for you.
Brian