Erro Cadastro

Veja isto

url da requisição (coloquei get pra poder depurar)
http://localhost:8080/blog/principal?nome=teste&usuario=teste&senha=123&action=Cadastrar&modulo=Usuario

protected void processRequest(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        try {
            request.setAttribute("Configuracoes", conf);
            if(request.getAttribute("Action")!=null)
                request.setAttribute("Action", request.getParameter("action"));
            RedirecionaModulo(request, response);
            
        
        
        } finally {            
            out.close();
        }
    }


    private void RedirecionaModulo(HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        String modulo= request.getParameter("modulo");
     
      if(modulo.equals("Usuario"))
          RedirecionaUsuario(request, response);
      else 
          response.sendRedirect("erro.jsp");
    }

private void RedirecionaUsuario(HttpServletRequest request, HttpServletResponse response)
            throws IOException, ServletException {
        String action =(String) request.getAttribute("Action");
       // request.setAttribute("Action", action);
        if(action.equals("Cadastrar"))
           response.sendRedirect("UsuarioAcoes");
          //  request.getRequestDispatcher("UsuarioAcoes").forward(request, response);
        else if(action.equals("Cadastro"))
            response.sendRedirect("UsuarioResultado");
        else {
            response.sendRedirect("erro.jsp");
        }           
    }