Comment 7 for bug 254064

Hi,
Using v0.4.0, I experience the same problem.
When running ubuntu-tweak as normal user, the "unlock" button in the "3rd party apps" or
"package cleaner" windows is available, but when clicking, says (dlg box) : "unable to authenticate, an unattended
error occured" (well, got it in french, it's my own english-translation there !)
When running as root, this button keeps being available, but clicking on it, I have no reaction.
Terminal logs :
damien@vostro:~$ sudo ubuntu-tweak
[sudo] password for damien: #######
You must not launch Ubuntu Tweak as root, it is INSECURE
## Yes we all know :-)
/usr/lib/python2.5/site-packages/apt/__init__.py:18: FutureWarning: apt API not stable yet
  warnings.warn("apt API not stable yet", FutureWarning)
Lecture des listes de paquets: Done
Lecture des informations d'état: Done
Lecture des informations d'état: Done
Lecture des informations d'état: Done
## these 4 previous lines were for package management, when accessing the add/remove feature
## there we go ! when clicking "3rd party" OR "package cleaner" :
Unhandled exception in thread started by <bound method PolkitButton.obtain_authorization of <PolkitButton object at 0x9e6970c (common+PolicyKit+PolkitButton+PolkitButton at 0x9ef2128)>>
Traceback (most recent call last):
  File "/usr/share/ubuntu-tweak/common/PolicyKit/PolkitButton.py", line 52, in obtain_authorization
    policykit = dbus.SessionBus().get_object('org.freedesktop.PolicyKit.AuthenticationAgent', '/')
  File "/var/lib/python-support/python2.5/dbus/bus.py", line 244, in get_object
    follow_name_owner_changes=follow_name_owner_changes)
  File "/var/lib/python-support/python2.5/dbus/proxies.py", line 241, in __init__
    self._named_service = conn.activate_name_owner(bus_name)
  File "/var/lib/python-support/python2.5/dbus/bus.py", line 183, in activate_name_owner
    self.start_service_by_name(bus_name)
  File "/var/lib/python-support/python2.5/dbus/bus.py", line 281, in start_service_by_name
    'su', (bus_name, flags)))
  File "/var/lib/python-support/python2.5/dbus/connection.py", line 607, in call_blocking
    message, timeout)
dbus.exceptions.DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Launch helper exited with unknown return code 1
## from this point, must force ubuntu-tweak to quit with a CTRL+C
## once I stopped the app, these lines appear :
Traceback (most recent call last):
  File "ubuntu-tweak.py", line 74, in <module>
    launcher.main()
  File "ubuntu-tweak.py", line 69, in main
    gtk.main()
KeyboardInterrupt

Hope helps !