Comment 2 for bug 994476

I'm sorry, I thought I'd seen this on my desktop, but come to think of it that was only on barebones server installs.

If you want pm-is-supported to work in libvirt, please install pm-utils

   sudo apt-get -y install pm-utils

and then restart libvirt

  sudo stop libvirt-bin
  sudo start libvirt-bin

It could be argued that pm-utils should be in libvirt's Suggests:, but I
think I prefer not to for a few reasons.