public function setOption($key, $value)
    {
        switch ($key) {
            case 'cellDecorator':
                $value = $this->getCellDecorators() + array($value);

            case 'cellDecorators':
                $this->_cellDecorators = $value;
                break;

            default:
                $this->_options[$key] = $value;
                break;
        }

        return $this;
    }