Install Xen on Virtualbox

Virtualbox is good choice if you just want to do a functional test of Xen, but don’t have the luxury of a dedicated PC.
I tried many times with Xen on Centos without success, Xen on Debian worked perfectly.
Environment:
- Hardware: RAM: ~1G RAM CPU:VT-X/AMD-V is optional (You can still test paravirtualization  guest[non-windows] without it)
- Host OS:WindowXP SP2 32bit
- Software: Virtualbox 4.0.0
- Xen Distribution: debian-507-amd64-netinst.iso
Install Debian on Virtualbox:
I just allocated 700MB RAM and select “Debian 64” as Virtualbox guest type, other settings were default
Install Xen kernel on Debian:

apt-get install xen-linux-system-2.6.26-2-xen-amd64 libvirt-bin virtinst

libvirt-bin virtinst are optional, they are third party tool to manage Xen.
 “(xend-unix-server yes)” in /etc/xen/xend-config.sxp need to be set in order for libvirt to connect to xen hypervisor. Otherwise following error will appear.

xen:/etc/xen# virsh
libvir: Xen Daemon error : internal error failed to connect to xend
libvir: Xen Daemon error : internal error failed to connect to xend
error: failed to connect to the hypervisor