Installing CentOS 5.2 on Dell PE1650

Twin Hitachi disks 36GB each (SCSI)

Created a single RAID 1 array /dev/md0 which is a mirror of the 2
disks

Then created a single root partition on /dev/md0 ( didnt bother with
swap because this is just for a test)

After the packages have been installed and the machine boots for the
first time I get GRUB error 22.

Have tried rescue mode and doing root(hd0,0) and setup (hd0)

No luck - it said it couldn't find stage2

Tried again on (hd1,0) and that seemed to work, but upon rebooting I
get the same error

Any ideas?