protected function getSortFields()
	{
		return array(
			'a.lft' => JText::_('JGRID_HEADING_ORDERING'),
			'a.published' => JText::_('JSTATUS'),
			'a.title' => JText::_('JGLOBAL_TITLE'),
			'a.access' => JText::_('JGRID_HEADING_ACCESS'),
			'language' => JText::_('JGRID_HEADING_LANGUAGE'),
			'a.id' => JText::_('JGRID_HEADING_ID')
		);
	}