Hello,
This question recently came up in the forums as well.
Here is an answer to it:
http://www.reactos.org/forum/viewtopic.php?p=34826#34826
Regards,
Colin
  From: ros-dev-bounces(a)reactos.org
[mailto:ros-dev-bounces@reactos.org] On 
Behalf Of Brian
  Sent: Thursday, August 30, 2007 4:33 PM
 To: ReactOS Development List
 Subject: [ros-dev] current status of xen support
 i was curious as to the status of reactos on xen. does it work(boot at 
all)? i
haven't seen anything new about it on the site, and i interested.
 thanks in advance
 --
 brian