Sawtooth won't shut down, restarts

[Anthony, Jason]

I have a g4 sawtooth that's been sorta Frankensteined. It has a 800 mhz
processor out of a Quicksilver, so I get a cache warning at bootup under OS9
but nothing unusual under OS X. It has been running fine for about 9 months,
but recently decided that it doesn't want to shut down. Here's the sitch:

OS X 10.28
1.5 gb ram
800 mhz G4, 256k cache
80 gb HD on an acard controller

When I choose "shut down", it restarts rather than shutting down. It sleeps
just fine, but if I want to shut it down I have to hold down the power
button on the case. I flashed the pram and the problem persists. Is there
some extension or something in OS X that could be causing this problem. Any
help is appreciated.

Thanks,
Jason