[et-mgmt-tools] Virt-manager won't connect to Xen hypervisor

[Steve Brueckner]

I've installed Fedora 7, Xen 3.1 (from source), and virt-manager 0.4 (from
rpms).  The machine is VMX/VT-x capable.  I have managed to build and run a
paravirtualized Linux guest just fine.  Now I want to build an HVM Linux
guest, but virt-manager tells me "unable to open a connection to the Xen
hypervisor/daemon."  I've confirmed that both xend and libvirtd are running.

Here are the error details:

------------------->8------------------
Unable to open connection to hypervisor URI 'xen':
<class 'libvirt.libvirtError'> virConnectOpenReadOnly() failed
Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/engine.py", line 68, in
_connect_to_uri
    conn = self.get_connection(uri, readOnly)
  File "/usr/share/virt-manager/virtManager/engine.py", line 309, in
get_connection
    conn = vmmConnection(self.get_config(), uri, readOnly)
  File "/usr/share/virt-manager/virtManager/connection.py", line 74, in
__init__
    self.vmm = libvirt.openReadOnly(openURI)
  File "/usr/lib/python2.5/site-packages/libvirt.py", line 109, in
openReadOnly
    if ret is None:raise libvirtError('virConnectOpenReadOnly() failed')
libvirtError: virConnectOpenReadOnly() failed
-------------------8<------------------

Can anyone see what I'm missing or what's broken?  If not, what should I do
next to debug or fix this?

Thanks,

Steve Brueckner, ATC-NY