Currently it is only possible to have the plugin filter WARs to make them 'skinny', however this could be very useful for other modules as well!
In my project I have both a WAR and a SAR that should share several libraries. As standalone artifacts, they should both package it themselves, but in the deployed EAR I get classloading-errors when they don't have the libs shared in the EAR.
I traced a solution to the method 'EarModule.getLibDir()', which is only implemented with a value in the 'WebModule'-subclass.
Since I am not familiar with all the module-types, I attached a solution that ONLY handles the SarModule, but this can probably used in all other Modules that contain libs as well.