ColdFusion.Tree.refresh

Has anyone got the ColdFusion.Tree.refresh ajax function to work, it keeps returning parent is null or not an object.

example (getmenu function returns a tree)

<script language="JavaScript">
function refreshtree()
{
ColdFusion.Tree.refresh('myTree');
}
</script>

<cfform name="OurTree">
<cfinput type="Button" name="refresh" value="refresh" onclick="javascript:refreshtree()">
<cftree name="myTree" format="html">
<cftreeitem bind="cfc:tree.getmenu({cftreeitempath},{cftreeitemvalue})">
</cftree>
</cfform>