How to request extended permission from a facebook fan page tab

I am trying to request permission to publish photos from a facebook fan page tab(iframe).

I am calling Facebook.showPermissionDialog('publish_stream'); before the upload(which doesn't seem to do much)

But I keep on getting this error when I try to upload a photo

**caught exception 'FacebookRestClientException' with message 开发者_运维百科'Permissions error'**

That's because the permissions aren't set. Had problems with this myself, but found a solution, maybe it's helpful for you: Stackoverflow

Get extended permission from user.See this