var nav=navigator.appName;
var ver=parseInt(navigator.appVersion.substring(0,1));
var kk=68-40;
if(nav.indexOf("Netscape")!=-1)
{
	if (ver < 5)
		kk=58-40 ;
}
if(nav.indexOf("Internet Explorer")!=-1)
{
        if ( document.body.clientHeight < 600 ) 
        { 
          kk=0;
        }
        else 
        {
          kk=(document.body.clientHeight-600) / 4;
        }
}
document.write("<table border='0'><tr ><td height='"+kk+"'></td></tr></table>");