Something between XFree86-4.2.0-6.48 and XFree86-4.2.0-6.51 broke my system, starting X just says something like could not find default font "fixed". The -6.48 and -6.47 versions work fine. My system is a RH7.2 with kernel and XFree86 updated from Rawhide (needed for ATI Radeon 7500 support). I'll provide more info if needed.
*** This bug has been marked as a duplicate of 61869 ***