I have changed the tooltip background color by changing the appearance theme from Ambiance to Adwaita.
I'm using Eclipse 3.6 for coding tasks. Now, when I use the command statement completion I see a tooltip that looks like this:
I am on ubuntu 12.04, using the unity3d desktop.
I searched for the ~/.gkrc* files and I searched in the /usr/share/themes/ folder... didn't find anything