The code belongs to ovof and is compilled by cabranail. ( osx86 community ) - i'm just passing it
The fix is for the grey little boxes that run osx and have more or two intel cores. It fixes the shutdown hangs by disabling all cores but one, making possible the shutdown. I know some of you use custom kernels with the same purpose, but this is cleaner (think of it as extending the kernel choices). It does not affect the restart in any way.
Install procedure :
-install chud.pkg (it is from xcode tools, free)
-install poweroff bug fix;
-that's it, enjoy, many thanks to the coder