autocomplete fill value instead of label on select.. why?

autocomplete fill value instead of label on select.. why?

Hi, this is my code:

  1. <div class="ui-widget">
  2.    <input id="places_autocomplete" />
  3. </div>

  1. $( "#places_autocomplete" ).autocomplete({
  2.         source: 'http://localhost/nightlife/events/events/get_all_places',        
  3.         select: function( event, ui ) {
  4.            
  5.         }
  6.     });

Don't know why, ONLY when item is selected from returned json data, it fills me up with the item value.
This does not happen until all labels are just proposed.

Why?