function selectItem(li) {
  if (li.extra && li.extra[1]) $("#wrapper").load("request.php", { 'cid': li.extra[1] } );
  else                         $("#ac_me").val('');
}

function formatItem(row) {
  if ( row[1] ) return row[0] + "<br><i>" + row[1] + "</i>";
  else          return "<b>" + row[0] + "</b>";
}

$(document).ready(function() {
  $("#ac_me").autocomplete("query.php", { minChars:3, matchSubset:0, matchContains:1, cacheLength:1, onItemSelect:selectItem, formatItem:formatItem, selectOnly:1 });
});