[CentOS] Problem installing Windows under Xen CentOS 5

Hi,

I'm having trouble installing Windows on a fully virtualized VM on
CentOS 5. The installation hangs on the blue screen saying "Setup is
starting Windows".
The hardware is a dual processor dual core AMD Opteron 2218 with 8GB
RAM and SATA disks, CentoOS 5 i386 will all patches applied. On the
same machine I have successfully installed two VM's running CentOS 5,
one paravirtualized and one with full virtualization.
I have tried to install Windows 2003 server and Windows XP with the
same result. The installation media are iso images of the Windows MSDN
DVDs.
When the installation hangs at the "Setup is starting Windows" screen
the virt-manager shows 25% cpu utilization for the guest ( I think
this represents 100% CPU usage for the guest as it has 1 vcpu assigned
out the maximum 4 vcpus).
I am running the virt-manager and the virtual machine console over ssh
as  dom0 has no X server installed.
Has anyone seen this problem? Any suggestions?

Regards,

Radu