You didnt get VoodooPS2 to work or you get the same stuck key side effect?
You need either ACPIPS2Nub+ApplePS2Controller OR VoodooPS2Controller, you cant have both installed at the same time.
The ACPIPS2Nub needs a stock ACPIPlatform (vanilla), also you need a version-independent ACPIPS2Nub (one that works with any ACPIPlatform, olders ones needed to be modded for each different ACPIPlatform version: i.e. you updated ACPIPlatform, you lost PS2 Devices...). Look for the one made by Chunnan/Eureka, theres a thread on insanelymac.; there is also alt kexts for situations like USB Keyboard+PS/2 Mouse, if thats what you have.
In any case a clean system (using a single set of PS/2 kexts, without mixing it all together) is advisable.
Also at least in my system Legacy USB Mouse & Keyboard BIOS otions has an effect on PS/2 support (for some unknown reason..).