Intel 82801FR SATA RAID controller ICH6R

[Gayn Winters]

I'm having trouble with RAID1 support on the ICH6R in a Tyan S5150
motherboard. I have two identical SATA 80GB Western Digital drives put
into a RAID1 array using the ICH6R setup.

I've tried both 5.4-RELEASE and 6.0-CURRENT-SNAP004 with the same
results.  Namely, via CD, the OS seems to load onto the mirrored SATA
drives without an error; however, when attempting to boot from the
resulting HDD the loader cannot find the OS and stops.  

If I disconnect the mirror using the ICH6R setup, the OS loads and boots
correctly - at least on 6.0 - and the OS sees both drives.

1.  Is the ata support (mk3 patches) now the same in 5.4 and 6.0?
2.  Is hardware (ICH6R) RAID1 mirroring supported?
3.  If "yes" to both, could I have corrupted the MBR?

Thanks,

-gayn