function show(menu_no)
        { 
          document.getElementById("menu"+menu_no).style.visibility="visible"; 

        }
        function hiden(menu_no)
        { 
          document.getElementById("menu"+menu_no).style.visibility="hidden"; 

        }

function reinitIframe(){

var iframe = document.getElementById("content_frame");

try{

var bHeight = iframe.contentWindow.document.body.scrollHeight;

var dHeight = iframe.contentWindow.document.documentElement.scrollHeight;

var height = Math.max(bHeight, dHeight);

iframe.height =  height;

}catch (ex){}

}

window.setInterval("reinitIframe()", 200);