Comment 22 for bug 48936

By the way, trawling the Ubuntu forums for this bug only turns up the "uncheck the 'Enable accessible login' checkbox in gdmsetup" solution, which has no effect.

Neither does disabling XDMCP, nor fiddling with the themes.

There is a small possibility that it has something to do with the font directory messages in the gdm log:

Could not init font path element /var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType, removing from list!

I'll try not to spam this thread again until I find something more substantial.