Yes, I've had the same thing. It started happening when I moved to FC2, don't know if its an xorg/XF86 thing. I seem to find that each time I run a kernel up2date, then reinstall the nVidia drivers I need to reinstall UT2004 otherwise it kills the x session on exit.
Bizarre, haven't really spent any time trying to debug it, too busy 'killin' UT2004 N00Bs !!