Zend_Config::__unset PHP Method

    public function __unset($name)
    {
        if ($this->_allowModifications) {
            unset($this->_data[$name]);
            $this->_count = count($this->_data);
            $this->_skipNextIteration = true;
        } else {
            /** @see Zend_Config_Exception */
            require_once 'Zend/Config/Exception.php';
            throw new Zend_Config_Exception('Zend_Config is read only');
        }
    }