How to re-install grub in a RAID 0 system

[Barry Yu]

A system with 2 SATA 160 gb hard drive configured with RAID 0 by Intel 
Matrix Storage Manager, XP pre-installed (F6 key SATA driver 
installation), I installed FC6 and during installation, FC6 actually 
detected all partitions as what XP detected and finally completed the 
installation, up and ran for a while, both XP and FC6 seeing this RAID 
configured volume as a single hard drive of 300gb (160gb x 2). Now the 
problem is;

I put an Ubuntu CD for live demo but got stuck during the initial start, 
this actually screwed up the system booting and the Grub will not work, 
I use the FC6 DVD and booted into rescue mode trying to do the 
grub-install, however I got message saying that can't find the BIOS 
driver (Can't remember exactly), I remember that during the installation 
of FC6, Grub was installed in /dev/mapping/xxxxxxxxxxxx something like 
that, but now when I do fdisk -l, I only can see that /dev/sda1 and 
/dev/sdb1 (If I remember correctly or close enough), grub-install 
/dev/sda will result "Can't find BIOS driver" .
Meantime, XP is up and running again after fix, but how to do the 
grub-install to put the grub back into system as boot