Comment 17 for bug 228690

I was about to mark this as affecting both the acpid and gnome-settings-daemon packages, but I've not had a chance to verify whether those are properly offering a 'shut down?' popup. If they do, then this isn't a bug.

If you install an ubuntu server as the guest, and install acpid (which won't be installed by default), then virsh shutdown does appear to work. You could also edit /etc/acpi/powerbtn.sh to not do the check for 'pidof PMS', but rather always call shutdown.

Please let us know if one of these works.