protected function getBorderForCell($rowIndex, $columnIndex)
    {
        $cell = $this->_table->getCell($rowIndex, $columnIndex);
        $border = $cell->getBorder();
        if ($border === null) {
            $border = new PHPRtfLite_Border($this->_rtf);
            $cell->setCellBorder($border);
        }

        return $border;
    }