function returnResult(http_request,handler) {
      if (http_request.readyState == 4) {
          if (document.getElementById('loading'))
            document.getElementById('loading').className='';
          if (http_request.status == 200) {
            var xmldoc = (http_request.responseXML);
            handler(xmldoc);
            
          }
      }
  
}
function fetchResult(resultId,handler,vars) {
  if (document.getElementById('loading'))
    document.getElementById('loading').className='visible';
  if (window.XMLHttpRequest) { // Mozilla, Safari, ...
      http_request = new XMLHttpRequest();
  } else if (window.ActiveXObject) { // IE
    
      http_request = new ActiveXObject("Microsoft.XMLHTTP");
  }
  http_request.onreadystatechange = function(){
    returnResult(http_request,handler);
  };
  //alert('./ajax_responder.php?respondTo='+resultId+vars);
  http_request.open('GET', '/user/js/ajax_responder.php?respondTo='+resultId+vars, true);
  
  http_request.send(null);
}