External keyboard disable

[Bober80]

Hello,

I have one task to disable any external keyboards wich will be connected by USB. But I have one internal keyboard which must work and this keyboard is connected by USB.

I need it for kiosk with internal keyboard and external USB, so users can use external USB port only for USB memory but not for connect external keyboard.

Is any way to disable any external keyboards and one internal keyboard should work?

I have Ubuntu 10.04 installed.

Thanks for advance.