Triple boot:XP,ubuntu&FC5 grub failed

[Gayal]

I was using Win XP with FC5 and wanted to install Ubuntu as well.

So i deleted the FC5 partition (just for the fun of doing it) and installed
ubuntu straight from the live cd V6.10.
And my laptop dual booted perfectly with XP.
After that i installed FC5 and during the creation of boot loader i added XP
and Ubutu as well from there respective partitions.

But then triple boot failed.
This is the message i get when selected ubuntu from Fedora Core 5 Grub Menu
-----------------------------------

Booting 'ubuntu'
rootnoverify (hd0,6)
chainloadre +1

Error 13: Invalid or Unsupported executable format.
Press any key to continue

so how can i fix this problem and tripple boot my laptop.

my file systems are as follows:
XP - NTFS
ubuntu - reiserfs
FC5 - Ext3

-- 
Gayal Rupasinghe
SRI LANKA
(SU-APIIT)
User #396462 counter.li.org