i found the following codes, it works for html,
but i don't know how to use them for php? where do i insert them to my zen cart? thanks

HTML Code:
<head> 
<script> 
function clear(){ 
Source=document.body.firstChild.data; 
document.open(); 
document.close(); 
document.title="hello"; 
document.body.innerHTML=Source; 
}</script> 
</head> 

<body onload=clear()> 
</body>