InfoPath Dev

I came across a site that shows how reset the forms data however when trying to impliment this I get an "Invalid procedure call or argument" exception on the final line of code.

var initialData;

function XDocument::OnLoad(eventObj)
{
 initialData = XDocument.DOM.selectSingleNode("/my:myFields/my:container").xml;
}

function CTRL3_5::OnClick(eventObj)
{
 // Load the initial saved XML into a DomDocument object
 var xmlDoc = new ActiveXObject("MSXML2.DomDocument.5.0");
 xmlDoc.loadXML(initialData);
 // Replace my:container
 var parentNode = XDocument.DOM.selectSingleNode("/my:myFields");
 var oldChildNode = parentNode.selectSingleNode("my:container");
 parentNode.replaceChild(xmlDoc.documentElement, oldChildNode);
}

I also ended up changing  MSXML2.DomDocument.5.0 to MSXML2.DomDocument.6.0 because when I was debugging I noticed that the xmlDoc.loadXML(initialData); returned false. the change from 5 -6 seems to have done the trick.

Any ideas on why this code doesn't appear to work?

Many thanks.

Finaly after much frustration, I got this code to work correctly.

 It seems this function needs xmlDoc.validateOnParse = false; before the initialData is loaded into xmlDoc.

What I don't understand is why would the DTD validation check on an XML segment change xmlDoc.documentElement to an invalid argument when if the check is not done the code runs through as expected?