Page with doctype not working

Hi,

I have this page:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml">
<head> 
<title>Teste </title>  

<link rel="STYLESHEET" type="text/css" href="Obj/Layout3.6/codebase/skins/dhtmlxlayout_dhx_skyblue.css">
<link rel="STYLESHEET" type="text/css" href="Obj/Layout3.6/codebase/dhtmlxlayout.css">

<script TYPE="text/javascript" src="Obj/Layout3.6/codebase/dhtmlxcommon.js" charset="windows-1250" ></script>
<script TYPE="text/javascript" src="Obj/Layout3.6/codebase/dhtmlxlayout.js" charset="windows-1250" ></script>
<script TYPE="text/javascript" src="Obj/Layout3.6/codebase/dhtmlxcontainer.js" charset="windows-1250" ></script>

</head> 

<script> 
 
function doOnload(){
dhtmlx.image_path='imgs/' ;
main_layout = new dhtmlXLayoutObject(document.body,'2E','dhx_skyblue');
var a = main_layout.cells('a');
a.setText('Aplicar');
a.setHeight('100');
a.setWidth('0');
main_layout.setCollapsedText('a', 'Aplicar');

} 
 
 </script>
<body onload="doOnload()" style="width:100%;height:100%;margin:0px;overflow:hidden;"></body> 

</html> 

If i take off the doctype code :

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 

My page work just fine, what could be?

thks

Hi
We recommend to use the next doctype: