Help please! Problem with insertBefore

Hi there,
I have an ASP script that uses the XML dom to take the values of HTML form fields and append them to my XML file. I want it to append my new field entries to the top of my XML file, so I am attempting to use the insertBefore method to insert my new field entries to the top of my file.
My XML file has a root element called "fanml" and a container element for each new entry called "news". How do I use the insertBefore method (in VB) to insert my new news elements before my old ones? (to the top of the file). I have tried using:
 objDom.insertBefore objNews, objRoot.childNodes(1)
But I get an error when I submit my form.

Any help is greatly appreciated.