firefox problem

[Jaime Alvarez <jalvarez ieee org>]

I was using Firefox 0.8 until i decided to try the new version 
yesterday. I used yum to remove the old one and then yum again to 
install version 0.9.1. Now i can't use either firefox or the original 
mozilla version that comes with Fedora (Core 1), but konqueror works 
fine. During the installation, yum said that a XFree86 update was needed 
and i agreed to it.

Any suggestions?