private void joinMeetingCallback(MeetingOutput output)
        {
            this.Dispatcher.BeginInvoke(delegate()
               {
                   if (output.status == "ok")
                   {
                       Meeting meeting = output.getEntity(server);
            //                       MDEDB.Meetings.InsertOnSubmit(output.getEntity(server));
                       MDEDB.Meetings.InsertOnSubmit(meeting);
                       MDEDB.SubmitChanges();
                       System.Diagnostics.Debug.WriteLine(meeting.ID);

                       //TODO go to the meeting page instead
                       MessageBox.Show("Succesfully joined the meeting.");
                       NavigationService.Navigate(new Uri("/Pages/MeetingPage.xaml?meetingID=" + meeting.ID + "&removePrevious=" + bool.TrueString, UriKind.Relative));
                   }
                   else
                   {
                       MessageBox.Show("Unable to join meeting.\nServer response:\n" + output.reason);
                       _timer.Start();
                   }
               });
        }