if self.get_field('urf:GlobalUserName') is not None:
            global_user_name = doc.createElement('urf:GlobalUserName')
            global_user_name.appendChild(doc.createTextNode(self.get_field('GlobalUserName')))
            global_user_name.setAttribute('urf:type', 'opensslCompat')
            user_id.appendChild(global_user_name)