Could you add linux-uksm-ck in your source?
XBMC shutdown/reboot polkit rules
I undid your modification to the XBMC page, as the polkit rule that enabes poweroff and rebooting when using the systemd service is not present in the current package, as you implied in your modification comment. You can check yourself here. Any reason you thought it was? I added a bug report mentioning this issue here. --Palmaway (talk) 03:31, 9 June 2013 (UTC)