R - install rattle (ubuntu/debian)

First add the line:
        deb http://debian.cran.r-project.org/cran2deb/debian-i386 testing/
or this (for 64 bit vers.)
         deb http://debian.cran.r-project.org/cran2deb/debian-amd64 testing/
to /etc/apt/sources.list

than type: sudo apt-get update

than you can finally install the package via:
sudo apt-get install r-cran-rattle