raid on sparc

Hi,

After 2 days of struggling with setting up RAID5 (mdadm) on Sparc, someone finally told me that the partition included in the array cannot start at sector 0 because raidtools overwrites the partition table. He also told me that mdadm should not have that problem, but from what I could see, that problem was very much there and only moving the partition to cyl 1 fixed it. Could someone please comment on this?
What I am trying to figure out is whether it is the raid partition that can't be on cyl 0, or any partition. I have a machine with 4 disks of which 3 are in a RAID5 array (no spare) and the forth has my /boot partition and the original root filesystem which is now on the array. I would like to eventually add this disk as a spare to the array but am am afraid that doing so will screw up my partition table since my /boot partition start at cyl 0.

On a related note, it would be very helpful to include this info in the HOWTO. Maybe a little note under the Devices section.

Thanks in advance.

Arshavir