I have a netbook with F17 installed.  No X, just text console. The system boots fine and the internal keyboard works.  I can plugin a USB numpad after boot and it functions reliably.  However, if the system is booted with the USB numpad attached the entire internal keyboard is frozen until the USB numpad's numlock key is pressed.  I've tried using usbreset and setleds to reset the numlock programatically - unsuccessfully.  The only thing that works is to press numlock on the USB numpad or unplugging and replugging.
Netbook w/ Fedora 17 and USB Numpad at Boot Disables Internal Keyboard
fedora;usb;keyboard