I have the same problem, SuSE 8.2 with TNT2 using 1.0-4363. Locks up randomly, usually after a few minutes of login. If I ssh in from another computer X is taking up ~98% cpu. If I kill the xserver it logs out the locked up session and the computer becomes usable again.
Happens with, for example, login and running only konqueror or login and running only kmail.