Hi, how can I make this code work for xanga?

<SCRIPT LANGUAGE="Javascript">

// ***********************************************
// AUTHOR: WWW.CGISCRIPT.NET, LLC
// URL: http://www.cgiscript.net
// Use the script, just leave this message intact.
// Download your FREE CGI/Perl Scripts today!
// ( http://www.cgiscript.net/scripts.htm )
// ***********************************************

function banner() {
};

banner = new banner();
number = 0;

// bannerArray
banner[number++] = "<a href="http://img178.imageshack.us/img178/4999/yoshibannerux6.jpg" target='_blank'><img src='http://www.doggiesite.com/phpBB2/viewtopic.php?t=46136' border='0'></a>"
banner[number++] = "<a href='http://www.doggiesite.com/phpBB2/viewtopic.php?t=46707' target='_blank'><img src='http://img.photobucket.com/albums/v691/Cially/airdried.jpg' border='0'></a>"


increment = Math.floor(Math.random() * number);

document.write(banner[increment]);

</SCRIPT>