Request processing failed; nested exception is java.lang.IllegalArgumentException: Expected MultipartHttpServletRequest: is a MultipartResolver configured?

Adicionei o MultipartResolver na classe AppWebConfiguration, mas continua mostrando o erro de request.

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.IllegalArgumentException: Expected MultipartHttpServletRequest: is a MultipartResolver configured? org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:894) org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:789) javax.servlet.http.HttpServlet.service(HttpServlet.java:660) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)

Class AppWebConfiguration

@EnableWebMvc 
@ComponentScan(basePackageClasses = {HomeController.class,ProdutoDAO.class})
public class AppWebConfiguration {    
    @Bean
    public InternalResourceViewResolver internalResourceViewResolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/views/");//setPrefix define o caminho onde estão nossas views
        resolver.setSuffix(".jsp"); //setSuffix adiciona a extensão dos arquivos views.
        return resolver;
    }

    @Bean
    public MessageSource messageSource() {
        ReloadableResourceBundleMessageSource messageSource =
            new ReloadableResourceBundleMessageSource();

        messageSource.setBasename("/WEB-INF/messages");
        messageSource.setDefaultEncoding("UTF-8");
        messageSource.setCacheSeconds(1);

        return messageSource;
    }

    @Bean
    public FormattingConversionService mvcConversionService(){
        DefaultFormattingConversionService conversionService = new DefaultFormattingConversionService();
        DateFormatterRegistrar formatterRegistrar = new DateFormatterRegistrar();
        formatterRegistrar.setFormatter(new DateFormatter("dd/MM/yyyy"));
        formatterRegistrar.registerFormatters(conversionService);

        return conversionService;
    }

     @Bean
        public MultipartResolver multipartResolver(){
            return new StandardServletMultipartResolver();
        }

}

Class ServletSpring MVC

public class ServletSpringMVC extends AbstractAnnotationConfigDispatcherServletInitializer{

    @Override
    protected Class<?>[] getRootConfigClasses() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    protected Class<?>[] getServletConfigClasses() {
        // TODO Auto-generated method stub
        return new Class[] {AppWebConfiguration.class, JPAConfiguration.class};
    }

    @Override
    protected String[] getServletMappings() {
        // TODO Auto-generated method stub
        return new String[] {"/"};
    }
     @Override
     protected Filter[] getServletFilters() {
          CharacterEncodingFilter characterEncodingFilter = new CharacterEncodingFilter();
         // characterEncodingFilter.setEncoding("UTF-8");
          return new Filter[] {characterEncodingFilter};
     }
      @Override
        protected void customizeRegistration(Dynamic registration) {
            registration.setMultipartConfig(new MultipartConfigElement(""));
        }

}

O método gravar da Class ProdutosController

    @RequestMapping(method = RequestMethod.POST)
    public ModelAndView gravar( MultipartFile sumario, @Valid Produto produto, Preco preco, BindingResult result, 
            RedirectAttributes redirectAttributes) throws SQLException{

        System.out.println(sumario.getOriginalFilename());

        if(result.hasErrors()) {
            return form(produto);
        }
        System.out.println(produto);
        produtoDao.gravar(produto,preco);
        redirectAttributes.addFlashAttribute("message","Produto cadastrado com sucesso!");
        return new ModelAndView("redirect:produtos"); 
    }