function updateCities () {
    selectedCounty = $('county').options[$('county').selectedIndex].value;
    selectedCounty = (selectedCounty == "") ? "all" : selectedCounty;
   	new Ajax.Updater('search_cities', '/idx/search.php?getCityList=' + selectedCounty, {
                      onComplete:function(request) { },
	      			  evalScripts:true, asynchronous:true });
}