UPDATE:

NOTICE TO ALL MCP68 + NfORCE630a / GeForce7025 / Shuttle SN68SG2 USERS!!!!!

In order to properly detect SATA on our platform using iPC, you must use the AppleVIAATA.KEXT NOT the AppleNforceATA.KEXT

I have not yet determined if applenforceata is still required for the cd drive and other IDE devices, but i'll figure that out shortly.