Strange Number Keypad problem

[Nat]

My number pad from my keyboard has been working sporadically and it seems
when it would be working for a few days, it would stop working on a restart.
I don't know what would trigger it but suddenly it would work again.  I
finally got tired of it and tried another keyboard but it wouldn't work.
Now I've tried every keyboard in the house, none of them work (just on the
number pad) and tried the same keyboards on another computer and they're
fine.

I'm running 10.2.6 on a G4 Quicksilver and I have Logitech's software for
that keyboard installed.  Could that cause all number pads to not work or is
this a hardware problem inside the computer?  I've never seen anything like
it.

Nat