Problem with IE 9 (changing the type attribute)

Hi all

i have this java script that with Firefox works fine but with IE9 don't work; any idea how to solve the problem ? Thanks in advance.

here the javascript
var element = e.srcElement || e.target;

if(element != null){
if(element.tagName == "INPUT") {

//alert("Before: " + element.getAttribute("type"));
element.setAttribute("type", "password");
//alert("After: " + element.getAttribute("type"));


}
}