Hi Beta,
I tried the DSDT with Mountain Lion 10.8.2 and the PS2 port seems to get disabled. My PS2 Keyboard was not detected. I have deleted the DSDT.aml from /Extra and my PS2 keyboard is detected.
I am using the following kexts from myHack for PS2 in /Extra/Extensions/
AppleACPIPS2Nub.kext
ApplePS2Controller.kext
If you can edit the DSDT.aml to have PS2 support, I can test it...
BTW, is there any advantage going for the DSDT method from non-DSDT? I suppose I'll have sleep, right?