Hi Don,
I finally figured out why xdm did not work for me.
It took me about 2 years.. but I finally found it! I
always used seven terminals (virtual) on the console,
ALT F1 through F7, and the X server for xdm is
hardcoded to start on the seventh terminal. Since the
two were conflicting, I could not use my keyboard and
it locked up. I just had to change the config file
/etc/X11/Xservers to point it to the eighth terminal.
I am no longer on the debian users list, so feel free
to post this reply if you feel like it.
Thanks
Aravind.