Setting query params to an array is not working

How do I set a query param to an array?

I have the following setup:

export default Ember.Controller.extend({
  queryParams: ['sort'],
  sort: null,

  actions: {

    onSortChanged(sort) {
      console.log('Sorting By: ', sort); // sort = ['name:asc']
      this.set('sort', sort);
    }

  }

});

But it renders as ?sort=name%3Aasc whereby I need it to render as ?sort[]=name%3Aasc