"The procedure bellow in general follows Thiago's
Martins submission  to xen-devel mailing list. However,sequence
of steps has been changed, /dev/xen/evtchn device hard linked with
with pvops kernel, git checkout procedure is more straight forward
and one Change-set from xen-4.0-testing.hg back ported to Xen 4.0
to support grub2 notation '(hd0,1)' specific for Ubuntu 10.04 aka
Lucid Lynx. The way as Xen 4.0 Dom0 set up worked on Ubuntu 9.10
(04) Servers doesn't work any longer.