I have the demo of the AutoComplete Combobox working on my site.  I am wondering how to trigger the onchange event of the underlying select when I choose a value in the autocomplete combobox.  I am using the exact code shown in the demo  http://jqueryui.com/autocomplete/#combobox when you click view source.

I'm guessing I have to trigger it in the below function but I'm not sure how,  Any suggestions?

2. this._on(this.input, {
3.                       autocompleteselect: function (event, ui) {
4.                           ui.item.option.selected = true;
5.                           this._trigger("select", event, {
6.                               item: ui.item.option
7.                           });
8.                       },
9. 
   
10.                       autocompletechange: "_removeIfInvalid"
11.                   });