non mi funziona sto codice. dovrebbe dare un alert al onfocus sul textarea .... boh?

codice:
<!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>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Documento senza titolo</title>

<style type="text/css">
body {background: #FFCCCC}

textarea{
	background: white;
	height: 140px; width; 200px;
	border: 1px solid #666;
	padding: 2px;
}
</style>

<script type="text/javascript">
document.onload = function(){
	var t_a = document.getElementById("shout");
	t_a.onfocus = function(){
		alert("ho preso il focus");
		}
	}
</script>

</head>

<body>

<form>
<textarea id="shout">ccc</textarea>
</form>



</body>
</html>