How to show field error in a Spring Roo custom controller' form - spring

Question

I am stuck with the following problem: error messages are not shown in the user form, but exist in the BindingResult. Need your assistance.
I am using the Spring Roo generated controller SignUpController
#RequestMapping("/signup/**")
#Controller
public class SignUpController {
List<ObjectError> signUpErrors;
#Autowired
private SignUpValidator validator;
#ModelAttribute("UserRegistrationForm")
public UserRegistrationForm formBackingObject() {
return new UserRegistrationForm();
}
#RequestMapping(params = "form", produces = "text/html")//, method = RequestMethod.GET)
public String createForm(Model uiModel) {
populateSignUpForm(uiModel, new UserRegistrationForm());
//uiModel.addAttribute("signUpErrors", signUpErrors);
return "signup/index";
}
#RequestMapping(method = RequestMethod.POST, produces = "text/html")
public String create(#Valid UserRegistrationForm userRegistration,
BindingResult bindingResult, Model uiModel, HttpServletRequest request) {
validator.validate(userRegistration, bindingResult);
if (bindingResult.hasErrors()) {
populateSignUpForm(uiModel, userRegistration);
//uiModel.addAttribute("signUpErrors", bindingResult.getAllErrors());
return "signup/index";
}
...
for a custom form-backing object UserRegistrationForm
public class UserRegistrationForm {
#NotNull(message="Must be filled.")
#Size(min=6, max = 45)
private String login;
#Email
private String email;
#NotNull
#Size(min=6, max = 45)
, try to validate it using custom validator. I can show error messages to users, directly passing BindingResults into the jspx, and using the code as follows:
<c:if test="${signUpErrors.size()>0}">
<util:panel id="title" title="${title}">
<h2>
<spring:message code="signup_index_error" />
</h2>
<p></p>
<c:forEach var="err" items="${signUpErrors}">
<br />
<tr>
<td>${err.objectName} </td>
<td>${err.codes} </td>
<td>${err.arguments} </td>
<td>${err.defaultMessage} </td>
</tr>
</c:forEach>
</util:panel>
<p></p>
</c:if
But the standart Roo and Spring tags doesn't work:
<field:input field="login"
id="fc_.._UserRegistrationForm_login" required="true"
z="" />
<sf:errors path="login" cssStyle="error"></sf:errors>
<field:input field="email"
id="fc_.._UserRegistrationForm_email" required="true"
z="" />
<sf:errors path="*" cssStyle="error"></sf:errors>