Comment # 1 on bug 978121 from Daniel Schunack

Sorry, here is the correct xml config...

XML VM Config
........
  <os>
    <type arch='x86_64' machine='xenfv'>hvm</type>
    <loader type='rom'>/usr/lib/xen/boot/hvmloader</loader>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
    <hap/>
    <nestedhvm/>
  </features>
  <clock offset='variable' adjustment='0' basis='utc'/>
........