how to multiboot xen with grub2 on Ubuntu

[Abhishek Dixit]

I installed Ubuntu 10.04  using Wubi installer inside a folder in
Windows7 in its C drive.

Following is one grub entry which perfectly works without any problem

menuentry "Ubuntu, Linux 2.6.32.27" {
       insmod ntfs
       set root='(hd0,2)'
       search --no-floppy --fs-uuid --set 96f65c80f65c6313
       loopback loop0 /ubuntu/disks/root.disk
       set root=(loop0)
       linux /boot/vmlinuz-2.6.32.27 root=/dev/sda2
loop=/ubuntu/disks/root.disk ro   quiet splash
       initrd /boot/initrd.img-2.6.32.27
}

To be able to use Xen I need to edit grub2 entries as per this page
http://bderzhavets.wordpress.com/2010/04/24/set-up-ubuntu-10-04-server-pv-domu-at-xen-4-0-dom0-pvops-2-6-32-10-kernel-dom0-on-top-of-ubuntu-10-04-server/
scroll down to grub section

So the entries which I have tried and failed to use Xen along with
grub2 are following

Entry 1 which failed is

menuentry "Xen Linux 2.6.32.27" {
       insmod ntfs
       set root='(hd0,2)'
       loopback loop0 /ubuntu/disks/root.disk
       set root=(loop0)
       kernel (hd0,2)/boot/xen.gz
       module (hd0,2)/boot/vmlinuz-2.6.32.27 dummy=dummy
root=/dev/sda2 loop=/ubuntu/disks/root.disk ro console=tty0
       module (hd0,2)/boot/initrd.img-2.6.32.27
}


Entry 2 which failed is

menuentry "Xen Linux 2.6.32.27" {
        insmod multiboot2
        set root='(hd0,2)'
        set root=(loop0)
        kernel (hd0,2)/boot/xen.gz dummy=dummy
        module (hd0,2)/boot/vmlinuz-2.6.32.27 dummy=dummy
root=/dev/sda2 loop=/ubuntu/disks/root.disk ro console=tty0
        module (hd0,2)/boot/initrd.img-2.6.32.27
}


I also tried  insmod multiboot  each time I got

error file not found
error unknown command 'kernel'
error unknown command 'module'
error unknown command 'module'

Any thing else which I can try?This seems to be a grub problem only.
-- 
Regards
Abhi