Shut down and power off primary and guest domain from command line

We use apcupsd to control the UPS ( apcupsd | A daemon for controlling APC UPSes )

When the power fails we want to shutdown all guest domains, then the primary domain, and finally power off.

This is so that if AC power is restored to the UPS, after the shutdown and power off, but before the UPS in totally drained (i.e. the base machine still has power to the PSU) , you can press the "ON" button on the base machine, or "power on" on the ILOM and the primary domain and guest domains will automatically start.

The problem is that "shutdown -i5 -y -g0" does not shutdown the guest domains.