X starts only in failsafe mode

I installed SuSE 8.2 minimal with X (TWM) and no KDE/Gnome. Later when my system hardware has been upgraded (RAM esp.), I installed KDE base, libs and utils. And now when I boot into INIT 5, kdm starts up but upon login I find that no matter which WINDOWMANAGER I choose (KDE/fvwm2/icewm) I always get into failsafe mode with a single instance of XTerm. I am able to run "exec startkde" or "exec icewm" and launch my window manager from there, but I would like to have kdm do this which is the normal procedure. Any ideas why X is always going into failsafe mode ? Thanks Vale