Comment random URL using Facebook graph API

Comment random URL using Facebook graph API

Is it possible to post a facebook comment for a random URL? I also want to
be able to display all comments for that random URL. I am using the
Android Facebook SDK.
I tried posting to this url:
http://graph.facebook.com/comments/?ids=[PAGE_URL]
but I get
errorMessage: (#100) Comments may not be added to a comment plugin
Am I doing something wrong or is there another way to enable users
commenting URLs from my app.