function stateChanged() 
  { 
   if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
   { 
   document.getElementById("txtHint").innerHTML=xmlHttp.responseText 
   } 
  }
  
  function GetXmlHttpObject()
  {
  var xmlHttp=null;try
   {
   // Firefox, Opera 8.0+, Safari
   xmlHttp=new XMLHttpRequest();
   }
  catch (e)
   {
   // Internet Explorer
   try
    {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
   catch (e)
    {
    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
   }
  return xmlHttp;
  }