Comment 1 for bug 877242

There's no gator-module package for lt-mx5 for the 5.7 release, so I believe you're just using the older one available at the PPA.

We'll have a newer kernel (3.1) for mx5 this cycle, and will request the LTs to enable the configs to be able to generate a pre-compiled gator-module package. Meanwhile you can try installing the gator-module-dkms package, but I believe it'll fail due missing config options.