I installed the KDE window manager on top of Ubuntu 11.10 and while I am using KDE, I do not get an elevation dialog when I try to perform tasks that require root privileges. Instead, the operations silently fail, unless I launch apps from a terminal, in which case I get errors like:

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/softwareproperties/gtk/SoftwarePropertiesGtk.py", line 649, in on_isv_source_toggled
    self.backend.ToggleSourceUse(str(source_entry))
  File "/usr/lib/python2.7/dist-packages/dbus/proxies.py", line 143, in __call__
    **keywords)
  File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 630, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: com.ubuntu.SoftwareProperties.PermissionDeniedByPolicy: com.ubuntu.softwareproperties.applychanges

Or from the muon package manager, an error dialog such as:

Does anyone know what I need to do to fix this, so that I get a proper dialog asking for elevation? Otherwise, I have to start each app that may need root privs with sudo from a terminal or gksudo.

Thanks