DOM Javascript - IE vs Firefox - hasChildNodes method

Hello.

I'm doing a javascript code using the function hasChildNodes. Here is a part of this code :

function indente(event) {
spanRow = eventTarget(event).parentNode.parentNode;
spanMain = spanRow.parentNode;
spanCloned = spanRow.cloneNode(true);
...
alert(spanCloned.childNodes[1].hasChildNodes());
...
}
function eventTarget(event){
if (event.target) return event.target;
if (event.srcElement) return event.srcElement;
}

I call this function like this :
<input type="button" id="indent" value=" > " onClick="javascript:indente(event)"/>

My problem is that on the alert box Firefox tells me 'true' and Internet Explorer tells me 'false'.

Where does it come from ?
Thanks for your help.
Mickael.

remove the javascript: from

onClick="javascript:indente(event)