I have Kubuntu 13.04 installed. KDE uses powerdevil to manage hibernate/sleep, which in turns seems to use
pm-utils is unmaintained, and broken at this point1. For example, I had to jump through many hoops to just enable in-kernel hybrid suspend which has been present since kernel 3.6.
I asked on Freenode #kde, and it seems like KDE powerdevil has been modified to accept newer backends for a while now. The order of preference is roughly systemd-login1, upower, and Solid.
Does anyone know what power backed will *buntu 13.10 use?
pm-utils code was last updated in 2010, and they have not been accepting patches.