Description of problem:

The latest libvirt/virt-manager combo creates xen configuration files with
a parameter xm doesn't recognize. An example of the offending line from an
/etc/xen file is:

  vfb = [ "type=vnc,vncunused=1,keymap=en_us" ]

Trying to 'xm create' the config file errors with:

  Error: configuration option keymap unknown to vfbs

This change came about via the patch to libvirt for bug 250789. In GA we used
the vfb[] format, but (at least by a default virt-manager guest install) the
keymap option was not present. So this could be a libvirt issue, but since xm
list --long shows the 'keymap' option coupled with the rest of the vfb options
in the sexpr, this option should probably be recognized by xm.

libvirt-0.2.3-7.el5
virt-manager-0.4.0-3.el5
xen-3.0.3-35.el5
xen-libs-3.0.3-35.el5
kernel = 2.6.18-37.el5xen

How reproducible:
Always

Steps to Reproduce:
1. Create a new guest in virt-manager
2. Shutdown the guest
3. 'xm create /etc/xen/GUESTNAME' and receive the error

Expected results:
No error, guest starts up.