How to expand associated entities in element binding

Hi

How to add provision to expand associated entities when doing a element binding

This is what I have done

_bindView: function(sObjectPath) {  // Set busy indicator during view binding  var oViewModel = this.getModel("detailView");
// If the view was not bound yet its not busy, only if the binding requests data it is set to busy again  oViewModel.setProperty("/busy", false);
this.getView().bindElement({  path: sObjectPath,     parameters:{expand:'EntityB'},  events: {  change: this._onBindingChange.bind(this),  dataRequested: function() {  oViewModel.setProperty("/busy", true);  },  dataReceived: function() {  oViewModel.setProperty("/busy", false);  }  }  });  },

But this does not seem to work.

Anything missing here?

Thanks

Sandip