Cannot install Rhel5.5 and Rhel 6 on same machine -- HELP PLEASE !!!!!!

Hi All,

I am new in linux. Stuck in a issue. Please help me.

I have already installed windoows 2008 R2 on the system. (/dev/sda1)
I have installed RHEL 5 in /dev/sda3 AND rhel 6 on /dev/sda6
I cannot install RHEL 5 and RHEL 6 on same machine. Following are the steps i did.

1. Installed RHEL 5 first and then RHEL 6.

While installing RHEL 6, I overwrite the MBR for Rhel 5.
I added entry for Rhel 5 while creating the grub during installation in Rhel 6. I mentioned the partition on which Rhel 5 was installed i.e. /dev/sda3
After successfully installing Rhel 6. When I tried to boot up in RHEL 5 from grub following error message was shown
"error 13 invalid unsupported executable format"

Following is the grub.conf file
[root@localhost ~]# cat /boot/grub/menu.lst
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You do not have a /boot partition. This means that
# all kernel and initrd paths are relative to /, eg.
# root (hd0,5)
# kernel /boot/vmlinuz-version ro root=/dev/sda6
# initrd /boot/initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,5)/boot/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux (2.6.32-71.el6.x86_64)
root (hd0,5)
kernel /boot/vmlinuz-2.6.32-71.el6.x86_64 ro root=UUID=d7f6cd43-646a-4c0f-8f15-5ea72583e6b5 rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=128M rhgb quiet
initrd /boot/initramfs-2.6.32-71.el6.x86_64.img
title rhel 5
rootnoverify (hd0,2)
chainloader +1
title Other
rootnoverify (hd0,0)
chainloader +1

I mounted the rhel 5 /dev/sda3 partition in RHEL 6. Checked the files are present in /boot folder. They were present.
Then I copied the rhel 5 grub.conf's ENTRY into Rhel 6 grub.conf.
This was the updated grub.conf file

[root@localhost ~]# cat /boot/grub/menu.lst
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You do not have a /boot partition. This means that
# all kernel and initrd paths are relative to /, eg.
# root (hd0,5)
# kernel /boot/vmlinuz-version ro root=/dev/sda6
# initrd /boot/initrd-[generic-]version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,5)/boot/grub/splash.xpm.gz
hiddenmenu
title Red Hat Enterprise Linux (2.6.32-71.el6.x86_64)
root (hd0,5)
kernel /boot/vmlinuz-2.6.32-71.el6.x86_64 ro root=UUID=d7f6cd43-646a-4c0f-8f15-5ea72583e6b5 rd_NO_LUKS rd_NO_LVM rd_NO_MD rd_NO_DM LANG=en_US.UTF-8 SYSFONT=latarcyrheb-sun16 KEYBOARDTYPE=pc KEYTABLE=us crashkernel=128M rhgb quiet
initrd /boot/initramfs-2.6.32-71.el6.x86_64.img
title rhel 5
root (hd0,2)
kernel /boot/vmlinuz-2.6.18-194.el5 ro root=LABEL=/1 rhgb quiet crashkernel=128M@16M
initrd /boot/initrd-2.6.18-194.el5.img
title Other
rootnoverify (hd0,0)
chainloader +1

STILL same error message was shown.

2. I installed Rhel 6 first and then RHEL 5.
While trying to boot Rhel 6 following error message was shown
"error 2 bad file or directory type"
I booted the system in RHEL 5 and again did all the things mentioned before. Still no output.

PLEASE can anybody help me out from this.

Thanks a lot