problem to create session of facebook

Question

try {
            HttpClient http = new HttpClient();
            http.setParams(new HttpClientParams());                             //http.getHostConfiguration().setHost("http://www.facebook.com/");
            http.setState(new HttpState());
            String api_key = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";                 
            String secret  = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";                 
//           String appId=124812364218050;                                      //http://www.facebook.com/developers/editapp.php?app_id=124812364218050
            FacebookRestClient client = new FacebookRestClient(api_key, secret);
            client.setIsDesktop(true);

//            String sessionKey = request.getParameter(FacebookParam.SESSION_KEY.toString());
//            boolean b = client.users_setStatus("This is a test...");
//            System.out.println("User Status RESULT : " + b);

        String token = client.auth_createToken();
        final String loginId = "http://www.facebook.com/login.php";
        GetMethod get = new GetMethod(loginId + "?api_key=" + api_key + "&v=1.0&auth_token=" +token);
        System.out.println("Get="+get);
        http.executeMethod(get);

        PostMethod post = new PostMethod(loginId);

        post.addParameter(new NameValuePair("api_key", api_key));
        post.addParameter(new NameValuePair("v", "1.0"));
        post.addParameter(new NameValuePair("auth_token", token));
        post.addParameter(new NameValuePair("fbconnect","true"));
        post.addParameter(new NameValuePair("return_session","true"));
        post.addParameter(new NameValuePair("session_key_only","true"));
        post.addParameter(new NameValuePair("req_perms","read_stream,publish_stream"));
        post.addParameter(new NameValuePair("email", email));
        post.addParameter(new NameValuePair("pass", password));


        System.out.println("Token ="+token);
        int postStatus = http.executeMethod(post);
        System.out.println("Response : " + postStatus);

        session = client.auth_getSession(token);                            // Here I am getting error
        System.out.println("Session string: " + session);
        long userid = client.users_getLoggedInUser();
        System.out.println("User Id is : " + userid);

    } catch (Exception e) {
        e.printStackTrace();

    }

please solve my problem i cannot create session of facebook.