Attachment file permalink by bbPress Attachments plugin
http://www.dreamfreeblog.com/bbs/
在 bbPress 官方论坛的一个求助贴，关于 bbPress Attachments 附件插件上传的文件会有一个很不友好的固定链接，在搜索引擎中显示不存在的页面，这种索引结果多了，很不利于 SEO，但愿论坛上有人解决这个问题。
http://bbpress.org/forums/topic/on-attachment-file-permalink
I have installed the bbPress Attachments plugin, it works fine to add a attachment, but the problem is that, the corresponding file will has a link like :
www.dreamfreeblog.com/bbs/ topic/18?bb_attachments=30&bbat=19
or
www.dreamfreeblog.com/bbs/ ?bb_attachments=24&bbat=13
as Google indexed page, actually as "Sorry, download is restricted."
Is there a method to avoid such permalinks except that to write a robots.txt rule for Google? Many thanks in advance! 
Check this thread in my bbPress for an example:
http://www.dreamfreeblog.com/bbs/topic/4
