Ubuntu – How to workaround the XFCE4 power manager being broken

I just did a clean install of 12.04 on my netbook, then installed xubuntu-desktop. (The reason for that is the showstopper bugs in 11.10 Unity — like menus not working, or the launch bar capturing the mouse and locking up the machine)

Now, the power button does nothing.
Attempting to go to power settings from the xcfe4 settings times out.

I checked, and xfce4-power-manager is running, as well as /usr/lib/upowerd.

Trying

sudo xfce4-power-manager --dump

does nothing for a minute or so, then gives me the following message:

ce4-power-manager:4226): xfce4-power-manager-ERROR **: 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.
Trace/breakpoint trap (core dumped)

along with the "crash" icon on the top panel, which I've now seen over 30 times in approximately 8 hours of uptime.

I'd be very interested in knowing how to get back up to the level of functionality that I had with 11.10 on this netbook.