I am having trouble installing Sabayon User Desktop Profile on Ubuntu 12.04. It errors out at - "configure: error: Please install Pessulus". When I try to install Pessulus, I get "configure: error: Package requirements (pygtk-2.0 >= 2.13.0) were not met:" "No package pygtk-2.0 found". I haven't been able to resolve this issue. Please help.