xen winxp guest image under fedora11 kvm host

[mantra UNIX]

Hi all,
I have a xen geust image (winxp) which i would like to use it under fedora
11/12 under kvm.

I know that i can use it, it works BUT its dam slow, dose any one know of
the tricks that would make it perform the same as it were under the Xen0