how to install multiboot.mod in grub of wubi

[Abhishek Dixit]

I installed ubuntu using wine,
here I need a module known as mutiboot in grub and I find this is missing.
I need it to boot Xen and other kernels.
Ubuntu was installed within C drive on Windows 7.

So how can I put the missing grub module as grub is not accepting command

grub> multiboot

or wubi installation does not uses grub2?
-- 
Regards
Abhi