protected function generateColumnHeader($column)
	{
		$params=$_GET;
		if(isset($params['sort']) && $params['sort']===$column)
		{
			if(isset($params['desc']))
				unset($params['desc']);
			else
				$params['desc']=1;
		}
		else
		{
			$params['sort']=$column;
			unset($params['desc']);
		}
		$url=$this->createUrl('list',$params);
		return CHtml::link(Post::model()->getAttributeLabel($column),$url);
	}