protected function getHelperMethodValue($helperMethodString, $args = null)
    {
        $helperName = explode('/', (string)$helperMethodString);
        $helperMethod = array_pop($helperName);
        $helperName = implode('/', $helperName);
        $helperArgs = [];

        if (!is_array($args)) {
            $helperArgs[] = $args;
        } else {
            $helperArgs = $args;
        }

        return call_user_func_array([Mage::helper($helperName), $helperMethod], $helperArgs);
    }