Ember.js + prototype.js conflict

we want to add a Ember.js-App to a existing site. The app is something like a widget what you integrate into your website. The website has prototype.js version 1.7.1 and our Ember.js-App has version 2.6 (but i tried 2.10 as well and the ember-twiddle uses 2.10).

Our problem is, that Ember seems to use the prototype Array instead of the Ember.js Array so methods like .clear() does not work properly because it calls the .clear() method from prototype.js instead that one from Ember.js.

Twiddle with prototype.js: http://ift.tt/2mp2KXt

Twiddle without prototype.js: http://ift.tt/2mbzk2I

If you click the "Output the .clear function to console" button to output the code of the .clear function. Those are different.

Shouldn't http://ift.tt/2moXpiX handle exactly what I want?

Does anyone know if that is intended or maybe a bug? Or am I missing something?

Thanks