Questo sembra funzionare con IE

codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

<html>
<head>
<title>Untitled</title>
</head>
<body>


<div id="areah">

</div>

<script language="JavaScript" type="text/javascript">
<!--
function attiva() {
 this.alt = ide;
}
pathName = "i1.jpg";
ide = "ciao";

var imagenode=document.createElement('IMG');	
   imagenode.setAttribute("src", pathName);
	 imagenode.setAttribute("onmouseover",attiva);
   document.getElementById("areah").appendChild(imagenode);
	 // alert(imagenode.onmouseover);

//-->
</script>
</body>
</html>