Grub + DualBoot + ChainLoader

[Morteza A. Nia]

I was installed FC2 on my PC (HDD with one Disk) , 1 month ago , but
on my friends' pc ( HDD with 2 disks) the Grub use chainloader for M$
WindowsXP but it couldn't  load WindowsXP by chainloder. and did not
know chainloader command on hda , .. ( else hda ).
if you know, so help me! ;)
Tanx.

Morteza A. Nia