[pubsubhubbub] http://pubsubhubbub.appspot.com does not return updated data to callback

[muhammed şahsuvaroğlu]

I am developing  pshb I subscribed using below data and I got 204
response from google think iti s ok
my callbackUrl is inside a network ,i put external ip of my network
was got from whatismyip.com


{
    "hub":"http://pubsubhubbub.appspot.com/subscribe";,
    "hubTopic":"http://friendfeed.com/?
auth=56kHFS0AMm9Fjj8f&format=atom",
    "callbackUrl":"http://78....:80/Pubsubhubbub/callback";
}

I have callback function implemented on java restful service like

     @POST
    @Path("/callback")
    @Consumes({MediaType.APPLICATION_ATOM_XML})
    @Produces("text/html")
    public Response callbackpost(InputStream is) throws
UnsupportedEncodingException, IOException {
        Writer writer = new StringWriter();
        System.out.println("!!!!!!"+is.toString());

      //  if (is != null) {


            char[] buffer = new char[1024];
            try {
                Reader reader = new BufferedReader(
                        new InputStreamReader(is, "UTF-8"));
                int n;
                while ((n = reader.read(buffer)) != -1) {
                    writer.write(buffer, 0, n);
                }
            } finally {
                is.close();
         //   }
            System.out.println("!!!!!"+ writer.toString());
        }
        ResponseBuilder  builder=Response.ok();

       return builder.build();
    }

When I updated myspace blog page, I wrote a feed but it doesn't come
into my service. Why?
what is the problem ,is it realted with ip?i have no clue related this
problem
i am looking forward to see your reply
thank you for your help