amd xorg driver not detected for Geode LX video controller

I'm running Gutsy on a thin client with a Geode LX video controller. When trying to install from the live image, I first select the "Start or Install Ubuntu" menu. Then, the progress bar shows that the image is being read. Finally, a prompt appears at the top left of the monitor and then it goes blank.

When trying to install from the alternate CD, the installation completes successfully. However, when the system reboots, the monitor is completely black. Even trying to change to other terminals with the Ctrl-Alt key sequence, the monitor remains black.

After rebooting in recovery mode, I noticed that the Driver for the graphics device was set to "vesa". Instead, I was expecting it to be set to "amd", especially since the amd driver is now distributed in main. So, I changed the Driver from "vesa" to "amd" and everything started working.

Therefore, there seems to be two problems:

1. The detection of the graphics controller doesn't recognize the Geode LX video controller.
2. The vesa driver doesn't work as a fallback for the Geode LX video controller.