title: onSubmit method of SimpleFormController does not submit for edit form
body: <p>I am implementing a simple Guestbook in Spring which allows me to delete and edit posts. I am using the same Form-View for both creating and editing a post. When I edit posts the form is prefilled with the data from the GuestbookEntry Object. For creating a new post the whole process works fine, but for the editing part clicking on the Submit button (which triggers onSubmit()) in my SimpleFormController does not redirect to the view I specified.</p>
  
  <p>This means that there a basically two different responses I get for the same form, using the same onSubmit() method.</p>
  
  <ol>
  <li>When creating a new post I click on Submit and I am being redirected to my guestbook.jsp View</li>
  <li>When editing a post I clock on Submit and nothing happens (there are also no exceptions being thrown)</li>
  </ol>
  
  <p>Here is the code of my onSubmit() method: </p>
  
  <pre><code>protected ModelAndView onSubmit(Object command) throws ServletException {
      Guestbook guestbook = (Guestbook) command;
      guestbook.setTimestamp(new Date());
      GuestbookHandler gbHandler = GuestbookHandler.getInstance();
      if(guestbook.getEntryId() != 0) {
          gbHandler.editGuestbookEntry(guestbook.getEntryId(), guestbook);
      } else {
          gbHandler.addGuestbookEntry(guestbook);
      }
      ModelAndView modelAndView = new ModelAndView("guestbook", "guestbookEntries", gbHandler.getGuestbookEntries());
      modelAndView.setViewName("guestbook");
      return modelAndView;
  
  }   
  </code></pre>
  
  <p>Any ideas?</p>