XML : Delphi Access Violation Setting IXMLNode

In the following contrived code snippet I get an access violation on the line marked //***

  procedure TWizardForm.MakeChanges;  var    XmlNodeNamedList: IXmlNode;    someInt: Integer;  begin    someInt := retrieveInteger();    XmlNodeNamedList := IXmlNode(someInt); // ***  end;    

This is very old code that I have inherited, that has been patched to "make it work" at some point. Any ideas why I would be getting an access violation?