NS_METHOD AppendChild(nsIDOMNode* aNewChild, nsIDOMNode** aReturn) { return NS_ERROR_FAILURE;
NS_METHOD AppendChild(nsIDOMNode* aNewChild, nsIDOMNode** aReturn) { return nsGenericElement::doInsertBefore(aNewChild, nsnull, aReturn);
  NS_METHOD AppendChild(nsIDOMNode* aNewChild, nsIDOMNode** aReturn) {    return NS_ERROR_FAILURE;  }