Upgrading policykit-1 to version 0.112-2 solves the problem (at least on my xfce4 system)!
After upgrading policykit-1/0.105-4 (sid) to 0.112-2 (experimental) the xfce4 logout shutdown/restart/suspend/hibernate buttons are no longer greyed out, the lightdm/1.8.5-1 shutdown/restart/suspend/hibernate buttons are showed again. The only remaining issue is that after a second login the lightdm restart and hibernate buttons have disappeared, shutdown and suspend are still there. -- To UNSUBSCRIBE, email to debian-bugs-rc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org