public function shim_addEventObserver($area, $eventName, $obsName,
            $type = null, $class = null, $method = null) {
        $eventConfig = new Varien_Simplexml_Config();
        $eventConfig->loadDom($this->_shim_getEventDom(
            $area, $eventName, $obsName, $type, $class, $method ));
        $this->_shim_getConfig()->extend($eventConfig, true);
        // this wouldn't work if PHP had a sane object model
        $this->_shim_getApp()->_events[$area][$eventName] = null;
        /* clear the event area cache because by the time this gets executed all <global> events have already been
           cached in Magento EE 1.11 */
        $this->_shim_getConfigShim()->unsetEventAreaCache($area);
        return $this;
    }