Getting PS2 keyboard to work

Need to borrow a USB keyboard.

In terminal:
cd /system/Library/Extensions/ApplePS2Controller.kext/Contents/PlugIns/

rename ApplePS2Mouse.kext and ApplePS2Trackpad.kext:
mv ApplePS2Mouse.kext ApplePS2Mouse.kext.bak
mv ApplePS2Trackpad.kext ApplePS2Trackpad.kext.bak

Leave ApplePS2Keyboard.kext alone.

Repair permission

cd /System/Library
sudo rm -rf Extensions.mkext Extensions.kextcache

reboot
Disable USB keyboard in BIOS.