Multibooting

[Wilson Woon]

Hi all....

I'm trying to install Windows XP, Fedora Core 3 and RedHat Linux 9 all
in one hard disk. At first I installed Windows XP and then Fedora Core
3. I use the Grub loader to load both of them. However, when it comes
to RedHat 9, I'm not sure how to do? How do I configure the Grub
loader so that it will detect RedHat 9 as well? Do I need to install
the Grub loader when installing RedHat 9 since  already have one?
How do I solve this problem? Please help. I don't mind reformatting
the whole HDD if necessary...

Thank you