extending ui modules

[ziolmar]

Firstly I would like to thank you for your great job with kraniumjs framework. We are using it to build our mobile app and right now all is going great.
I have only one small question, about extending UI modules, I hope you could help me.

I want to extend Window module to add some new functions and I want that all new windows have this function.
So I can create file gswindow.js where I placed:

exports.Class = Window.extend({
init: function(o){
.....
this._super(o);
},
someFunction: function(){
alert('test');
}
});

And now I would like to create for example login window, so I would like to extend gswindow (from above), like this:

exports.Class = gswindow.extend({
init: function(o){
.....
this._super(o);
}
});

I'm wondering how to achieve such behaviour? Please help :)