Comment 59 for bug 565543

The problem appears to be in the kernel - your Alps touchpad devices appear to not be tagged with the TOUCHPAD variable. This means that the Xorg Synaptics driver won't load for your touchpad - it is set up to load for all touchpads, and since your touchpad isn't tagged as a touchpad the Synaptics driver isn't loading.

Finding the precise kernel which broke the touchpad tagging would be helpful, since this is apparently a regression. You can find all the kernel versions which have been released to Lucid on the kernel's Launchpad page¹. Finding the last kernel which works, and the first kernel which doesn't will help narrow down what change broke this.

1: https://edge.launchpad.net/ubuntu/lucid/+source/linux