I just tried to find a solution for dual monitorsetup, installing gconf-editor and "additional drivers" on my ubuntu 12.10 cairo-dock desktop laptop. actually I deinstalled my bluetooth programms ...
I am running Ubuntu 12.04. on a Lenovo Thinkpad T400. I connected an external monitor as a second display. The laptop stands under the external screen. The laptop has a native resolution of 1440x900 ...