if i make leopard partiton active and xp inactive.. i get "MISSING OPERATING SYSTEM"

Tried to rewrite MBR.. it didnt help.. i get no bootloader.. just boots into xp..

i booted into a bootable cd for active partition recovery (data backup) where it gives info on all partitions and for the leopard partition is said "error reading sector # 0 or boot sector is invalid"

i also booted into a bootable cd for partition table doctor and there i found this abt the partitions --

Partion cylinder Head Start
XP 0 1 1
leopard 1362 0 1

i hope this helps u to help me..

thanx..