RHEL 6.1 KVM Windows XP guest disk IO rate problem

I have an IBM HX5 blade server pair (2 combined) with a total of 4 50GB solid sate drives.  I have loaded the system using a "standard" LVM configuration and have also tried RAID 0.  After installation of a KVM Windows XP guest, for both types of system OS loads, the guest disk I/O rate is greatly reduced.  I understand that a "virtio" disk should be used to support the para-virtualized drivers but there doesn't seem to be support for this during OS installation.  For the "standard" load, the guest VM disk rate is less than half the host disk rate.  The guest VM disk rate never changes even when a host RAID 0 is used.  Is there anything that can be done to increase this guest disk rate?

Thanks for any help

Jerry