Shutdown/Restart from gdm fails silently with 2+ users logged in

Binary package hint: gdm

When more than 1 user is logged in, selecting 'Restart' from the power menu on gdm does not do anything and returns no error. When restarting from within a session when more than 1 user is logged, a dialog is thrown asking for elevated privileges to confirm the action, but this does not happen while in gdm.

Steps to reproduce:

Login as user1
Switch back to gdm and login as user2 as well
Switch back from user2 to gdm and select restart

What I expected to happen

Login as user1
Switch back to gdm and login as user2 as well
Switch back from user2 to gdm and select restart
Dialog popped asking for credentials of an admin user
System restarts

I'm pretty sure this happens with shutdown as well, I will test that now and amend this report

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: gdm 2.30.0-0ubuntu3
ProcVersionSignature: Ubuntu 2.6.32-16.25-generic
Uname: Linux 2.6.32-16-generic i686
Architecture: i386
Date: Tue Apr 6 05:23:56 2010
InstallationMedia: Ubuntu 9.10 "Karmic Koala" - Release i386 (20091028.5)
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: gdm