Mouse freeze during kde boot

Hi! I've got a problem with a Packard Bell notebook which touchpad works but not as expected.
If i normally boot into Knoppix (loading kde as default) the mouse works till kde initialize it himself
and then freeze the entire system.
If i boot and choose another wm (iceWM for example) all is fine and works ok.. so i think it's not
an hardware or Bios fault.
I'd really like to understand what's wrong with kde! am i missing something important?
Sorry to bother and thank you in advance.

Juzam