Schedule halt using ConsoleKit and Dbus

I have been playing with Dbus (versions 1.4.0, in Ubuntu 10.10 and 1.4.14) and ConsoleKit (versions 0.4.1 and 0.4.5) to reboot or halt my computer without being a superuser. Everything works fine in both versions. If I execute the commands detailed in this page , the systems halts or reboots without troubles. Now, what I'd like to know is whether I can schedule that halt/reboot at a certain time (still using Dbus/ConsoleKit). Something like the shutdown command can do (shutdown -h 10:56) Is that possible? I can always use an at or cron, but if I can do it straight with dbus, that'd be perfect.