The company now offers the SPICE drivers for KVM virtual machines.
The package (for Windows XP only at the moment) creates a virtual GPU called Red HAt QXL and a Virtual Desktop Interface Port.
Administrators are also required to install a SPICE agent inside each Windows guest.
At that point the SPICE client, which is part of the open source release, will be able to connect to the virtual machine.
Thanks to Linux-KVM for the news.