title: "Cannot execute task: the task is already running" even when I create a new request object
body: <p>I have a loop that calls the getComments method for each Facebook object as shown, the getComments method is not called from anywhere else in the program.</p>
  
  <pre><code>JSONArray feedArr = response.getGraphObject().getInnerJSONObject().getJSONArray("data");
  for (int i=0;i&lt;feedArr.length();i++) {
      JSONObject obj = feedArr.getJSONObject(i);
      getComments(obj.getString("id"));
  }
  </code></pre>
  
  <p>From what I see, I am making a new Request object each time, but I still get the error <code>"java.lang.IllegalStateException: Cannot execute task: the task is already running."</code> each time. </p>
  
  <pre><code>private void getComments(final String post) {
          String fqlQuery = "{" +
                    "'comments':'SELECT fromid, text, id, likes, time, user_likes FROM comment WHERE post_id=\""
                    + post + "\" LIMIT 2000'," +
                    "'users':'SELECT uid, name, pic_square FROM user WHERE uid IN (SELECT fromid FROM #comments)'" +
                    "}";
  
          Bundle params = new Bundle();
          params.putString("q", fqlQuery);
  
          Session session = Session.getActiveSession();
          new Request(session, 
              "/fql", 
              params, 
              HttpMethod.GET, 
              new Request.Callback(){ 
              public void onCompleted(Response response) {
                  //..parsing data
              }
          }).executeAsync();
      }
  }
  </code></pre>
  
  <p>Is there a reason why this happens and how can I fix it?</p>