You will need to install two kexts (ATIinject.kext and ATINDRV.kext plus modify the SL kext ATIRadeonX1000.kext.
1st) Backup you original ATIRadeonX1000.kext. I have actually made a backup of all my extensions as follows
CODE
sudo mkdir -p /Backups/Extensions/
sudo cp -r /System/Library/Extensions/* /Backups/Extensions/
sudo cp -r /System/Library/Extensions/* /Backups/Extensions/
2nd) I used the following versions of ATIinject.kext and ATINDRV.kext: http://www.megaupload.com/?d=NT8WW4CE
3rd) You have backed up your orginal kext right? If not see step #1. Now using either vi or Property List Editor, open ATIRadeonX1000.kext/Contents/Info.plist. When you have this open find the entry IOPCIMatch and add your identifier 0x71D41002 to the list. Save the file.
4th) Next using a hexeditor such as 0xED or Hex Fiend open up ATIRadeonX100.kext/Contents/MacOS/ATIRadeonX1000. Search for the following hex string DE 71 and replace it with D4 71. You should replace it 4 times at the following offsets 184870, 391608, 719902, and 904948. Save the file.
5th) Now regenerate your extensions cache and reboot. You should now have resolution changing support and QE/CI. A quick way to check QE/CI is to try to view a jpg file with preview or take a screenshot with Grab.app if both of them display then you have QE/CI. Enjoy!