I have done a bunch of testing and NetworkManager does not send the
client-host's name to the server so that an IPv6 dns entry can occur. I
have dupicated the problem with dnsmasq and bind/dhcp.
This has been reported:
https://bugzilla.redhat.com/show_bug.cgi?id=858327
Now back to figuring out how to get IPv6 dhcp support into libvirt.
Gene