I think that's my com.apple.boot.plist . If you need to re-write it "like that one" why not use that one?
Download this package http://www.tonymacx86.com/Public/Cha...eBLN-1.1.9.zip and select your snow leopard disk (partition) and install. ATENTION: IF YOU HAVE A OTHER OS (LIKE LEOPARD OR WINDOWS) ON THAT DRIVE IT WILL BE MODIFIED AND YOU PROBABLY WONT BE ABLE TO BOOT IT!
Then put a "good" DSDT in and the right kexts and your ready to go!