Fedora xen - Jul 2007 - libvir: Xen Daemon error : GET/POST operation failed:

When I try to install a guest on 64bit FC7 I get the error below. Any
ideas?

# virt-install
Would you like a fully virtualized guest (yes or no)?  This will allow
you to run unmodified operating systems. yes
 What is the name of your virtual machine? fedora
 How much RAM should be allocated (in megabytes)? 500
 What would you like to use as the disk (path)? /dev/vg01/LVfedora
 Would you like to enable graphics support? (yes or no) no
 What is the virtual CD image, CD device or install location?
http://ftp.usf.edu/pub/fedora/linux/core/6/i386/os/


Starting install...
libvir: Xen Daemon error : GET operation failed:
Retrieving Fedora...      100% |=========================|  849 B   
00:00
Retrieving boot.iso...    100% |=========================| 7.9 MB   
00:12
libvir: Xen Daemon error : GET operation failed:
libvir: Xen Daemon error : POST operation failed: (xend.err ''Device
5632 (vbd) could not be connected. losetup -r /dev/loop0
/var/lib/xen/virtinst-boot.iso.Kkp7nL failed'')
Traceback (most recent call last):
  File "/usr/sbin/virt-install", line 629, in <module>
    main()
  File "/usr/sbin/virt-install", line 578, in main
    dom = guest.start_install(conscb,progresscb)
  File "/usr/lib/python2.5/site-packages/virtinst/Guest.py", line 649,
in start_install
    return self._do_install(consolecb, meter)
  File "/usr/lib/python2.5/site-packages/virtinst/Guest.py", line 666,
in _do_install
    self.domain = self.conn.createLinux(install_xml, 0)
  File "/usr/lib64/python2.5/site-packages/libvirt.py", line 503, in
createLinux
    if ret is None:raise libvirtError(''virDomainCreateLinux()
failed'',
conn=self)
libvirt.libvirtError: virDomainCreateLinux() failed POST operation
failed: (xend.err ''Device 5632 (vbd) could not be connected. losetup -r
/dev/loop0 /var/lib/xen/virtinst-boot.iso.Kkp7nL failed'')