No privilages to perform many actions from desktop

Summary:
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I recently performed a dist update via update-manager to install 10.4, since the install, I have not been able to perform any action that requires elevated privileges from the desktop, such as changing the CPU step via CpuFreq applet, Log off/Shutdown/Sleep/Hibernate via the Shutdown applet, and SD Card/USB drives are not auto mounting.

I can perform privileged actions via sudo in a terminal.

dmesg/syslog showed nothing interesting to me (maybe someone can see something useful there)

however there were some interesting error messages among other messages in .xsession-errors:

(polkit-gnome-authentication-agent-1:1413): GLib-GObject-WARNING **: cannot register existing type `_PolkitError'

(polkit-gnome-authentication-agent-1:1413): GLib-CRITICAL **: g_once_init_leave: assertion `initialization_value != 0' failed
Screen isn't composited

Google:
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I googled around for some time in hopes of finding a quick solution, and found some issues that seemed similar to what I am encountering.

http://ubuntuforums.org/archive/index.php/t-812066.html
Bug #445303
Bug #540769
Bug #482875

However none of the suggested fixes helped resolve my issue.

Other Interesting Things to Note That May Be Related:
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When running polkit-gnome-authorization (either as my self, or as root) I only see 4 tree nodes: (Revoke,Read, Modify and Grant Authorizations to other users) nothing else.

When I run users-admin as my self I can not change any of my privileges. If I run it with sudo I see the following message on stdout and i am then able to modify my privileges.

~ > sudo users-admin
[sudo] password for pat:

(users-admin:5222): Liboobs-WARNING **: There was an unknown error communicating asynchronously with the backends: Did not receive a reply. Possible causes include: the remote application did not send a reply, the message bus security policy blocked the reply, the reply timeout expired, or the network connection was broken.

I only have awn in my local .config/autostart/ directory
~ > ls .config/autostart/
awn.desktop

I attempted to edit my hal.conf by adding copying all the entries under the "root" user tag, under the default tag. with no effect. and I also "aptitude removed hal" with still no change.

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: ubuntu-desktop 1.197
ProcVersionSignature: Ubuntu 2.6.32-22.33-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic i686
Architecture: i386
Date: Thu May 13 17:07:24 2010
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-meta