400 Bad Request Error

Since a few days ago whenever I try to log in on the forums, I keep getting the 400 Bad Request error. Odd part is, it only happens when I try through Firefox (3.6 version). But this does not happen when I use IE (which is what I'm using to post this), does this happen to anyone else/does anyone know how to fix it?

Yep, that fixed it, thanks a bunch