OK, I saw your problems from your own IOReg. Thanks for sharing. That help me a lot to make a better dsdt for the 6820s.
First of all, READ THE WHOLE THREAD PLAESE... so, after read the post you will understand that you don't need the X3100 (intel) plugin inside FakeSMC (show package content), please see the capture. You can erase it, wait about 3 minutes, and then rebuilt cache running kextutility.app once, that operation repair automatically the permissions too. I think, after reboot you should go to sleep w/o problems because that plugin is unnnecesary and problematic (for me, too many problems) give me randoms KP all the time, and from a couple a months Im back to using the netkas one (refake by me) attached, please consider that "tjmax" of my Merom CPU is 100C (info.plist). Note: all my .kext are installed on /S/L/E (OPTIONAL).
Second and I repeat: READ THE WHOLE THREAD PLAESE (at least from May 01/2010). So, when you try go to sleep, are you see the blue light blinking intermittently? Sorry but, are you sure you have SleepWatcher running?
Third, wait the dsdt.aml test2. I will correct/add/optimize the dsdt based in your .ioreg... I will post later today.
EDITED: DONE! Please upload new .ioreg