autocomplete + select

autocomplete + select

Hi at all
I'm using jquery autocomplete to fill a textbox with some text but I need to get the ID of the item too
for this purpose I thought to use the on select event to fill an hiddend field
the problem is that the on select event is never fired
this is my code

  1. $(function() {
       $('input#<%= tblNewInsert.FindControl("nazioni").ClientID %>').autocomplete({
           source: function(request, response) {
              $.ajax({
               url: "offerte.aspx/fillJson",
               data: "{ 'descrizione': '" + request.term + "', 'tabella': 'nazioni', 'campo': 'paese' }",
               dataType: "json",
               type: "POST",
               contentType: "application/json; charset=utf-8",

               select: function(event, ui) { alert("never fired"},

               success: function(data) {
                   response($.map(data.d, function(item) {
                   return {
                   value: item.descrizione                                                          
                   }
                  }))
               },
              
           error: function(XMLHttpRequest, textStatus, errorThrown) {
             alert(textStatus);
               }
            });
          },
          minLength: 1
       });
         
    }); 





























what is wrong?

thank you
Marco