NS4 = (document.layers); 
   IE4 = (document.all); 
  ver4 = (NS4 || IE4);    
 isMac = (navigator.appVersion.indexOf("Mac") != -1); 
isMenu = (NS4 || (IE4 && !isMac)); 

function popUp(){return}; 
function popDown(){return}; 
function LetsGo(){return}; 
if (!ver4) event = null;