[libvirt] Paused networking on VM up/down with NAT fwd

Hi all, some time ago bug https://bugs.launchpad.net/ubuntu/maverick/+source/qemu-kvm/+bug/584048 was fixed in libvirt. It's the one where when a VM is started or stopped which has a lower macaddr than what the bridge currently has, the bridge changes macaddr and networking pauses. The fix was to make sure that a macaddr assigned by libvirt will start with 'fe:' making it higher than the physical interface. But this doesn't help when virbr0 isn't associated with any physical nic, as in the common NAT case! Is there anything we can do to help that case? thanks, -serge