JSR 303 Bean Validation + Javascript Client-Side Validation

Here's how I'm doing it using Spring MVC + JQuery + Bootstrap, partially based on a recent blog post at SpringSource:

AddressController.java

@RequestMapping(value="/validate")
public @ResponseBody ValidationResponse processForm(Model model, @Valid AddressForm addressForm, BindingResult result) {
    ValidationResponse res = new ValidationResponse();
    if (result.hasErrors()) {
        res.setStatus("FAIL");
        for (ObjectError error : result.getAllErrors()) {
            if (error instanceof FieldError) {
                FieldError fieldError = (FieldError) error;
                res.addError(fieldError.getField(), fieldError.getDefaultMessage());
            }    
        }
    }
    else {
        res.setStatus("SUCCESS");
    }
    return res;
}

AddressForm.java

public class AddressForm {
    @NotNull
    @Size(min=1, max=50, message="Address 1 is required and cannot be longer than {max} characters")
    private String address1;

    @Size(max=50, message="Address 2 cannot be longer than {max} characters")
    private String address2;

    // etc
}

ValidationResponse.java:

public class ValidationResponse {
    private String status;
    private Map<String,String> errors;
    // getters, setters
}

address.jsp:

<f:form commandName="addressForm">
    <div class="control-group">
        <label for="address1">Address 1</label>
        <div class="controls">
            <f:input path="address1" type="text" placeholder="Placeholder Address 1" c