Dual Vista - MacOSx and Raid1 on 4 drives

Hi,

i have the following 4 psychical SATA2 drives:
1 x WD Raptor 37GB (Disk1)
1 x Seagate Barracuda 120GB (Disk2)
2 x Samsung 500GB (Disk3 + Disk4)

Bios: Sata Mode>> ACHI

I have installed on Disk1 the MACOS 10.5.3
On Disk2 Vista Professional SP1.

The system runs and boots perfect from both OS

I want to create the following partitions on the Disks 3+4
Disk3
1 x 300GB   (disk3_a)
1 x 37GB   (disk3_b)
1 x 163   (disk3_c)

Disk4
1 x 300GB  (disk4_a)
1 x 37GB   (disk4_b)
1 x 163   (disk4_c)

Then i have to create:
RAID1 for Data files when working with Mac, between: "disk3_a" + "disk4_a"    (300GB)
RAID1 for Backing up the MAC OS, between: "disk3_b" + "disk4_b"    (37GB), and finally
RAID1 for Data files when working with Vista, between: "disk3_c" + "disk4_c"    (163GB)

Firstly i go into Mac, create the 3+3 partitions (using DiskUtility) on Disks3+4  (GPT partition table)
I successfully create the 1st and 2nd mirrored volumes (HFS+)
I leave the last 1+1 partitions "disk3_c" + "disk4_c", unformatted so i can later format them under Vista (NTFS)

I boot into Vista
I can't create with this type of partition table (GPT) my third mirrored volume!

On the other hand if i split the drives using MBR table, i can't create mirrored RAID1 volumes under MAC

Is it true that the MAC OS can't create RAID1 volumes from drives with MBR table?!

Is there any other procedure i can follow for creating those 3 mirrored RAID1 volumes?!