Dependency problem on ubuntu 15.04 for ROS Jade

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I am facing a problem while following the ROS installation procedure from here. When I reach the step 1.4 and type :

sudo apt-get install ros-jade-desktop-full

I'll get this error :

sudo apt-get install ros-jade-desktop-full
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 ros-jade-desktop-full : Depends: ros-jade-simulators but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

The purple part in the tutorial is supposed to help with dependency issues but it is not related to 15.04 and they didn't help me anyway. Needless to say, it is also not possible to only install ros-jade-simulators or ros-jade-desktop-base