I have the same problem. Whenever I start X (always by means of xdm),
my keyboard locks up. If I repeatedly unplug and replug the keyboard,
eventually (takes from 2 to 20 iterations) I'll hear the disk churn
for a fragment of a second and then I'll be able to type again.

I figure since there's disk activity of some kind when typing ability
is restored, it might be some sort of race condition between XFree86's
keyboard driver and NetBSD's, but I've had no luck nor spent much
effort trying to track it down.

-Zach Fine
czyz@u.washington.edu