ASP.NET MVC3 Eager Client-Validation, FluentHTML and Nested ViewModels

I'm using FluentHTML (from MvcContrib) to layout my HTML mark-up. I want to use eager unobtrusive client-validation provided by jquery.validate library. I got everything working correctly except for properties of nested ViewModels. Example:

public class RegisterPageViewModel
{
    [Required(ErrorMessage = "First Name cannot be empty.")]
    public string FirstName { get; set; }

    [Required(ErrorMessage = "Last Name cannot be empty.")]
    public string LastName { get; set; }

    [Required(ErrorMessage = "Email cannot be empty.")]
    [RegularExpression(@"^\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$", ErrorMessage = "Invalid Email Format.")]
    public string Email { get; set; }

    [Required(ErrorMessage = "Password field cannot be empty.")]
    [DataType(DataType.Password)]
    public string Password { get; set; }

    [Required(ErrorMessage = "You have to confirm your password.")]
    [Compare("Password", ErrorMessage = "Passwords must match.")]
    [DataType(DataType.Password)]
    public string PasswordConfirm { get; set; }

    [Required]
    public AddressDto Address { get; set; }

    public bool TermsOfUse { get; set; }

    [Required(ErrorMessage = "Nickname is required")]
    public string Nickname { get; set; }

    public string MiddleName { get; set; }

    [Required(ErrorMessage = "Birthdate is required")]
    public string Birthdate { get; set; }

    public string Phone { get; set; }

    [Required(ErrorMessage = "Mobile num开发者_JAVA百科ber is required")]
    public string Mobile { get; set; }

    public string RakimMelieh { get; set; }

    public string ReferralNickname { get; set; }
}

It works perfectly for ALL of the properties except for those inside the Address property, although I decorated the properties of the AddressDto with validation attributes as well:

public class AddressDto
{
    public int Id { get; set; }
    [Required(ErrorMessage = "Address Name is required.")]
    public string Name { get; set; }
    public string Country { get; set; }
    public string District { get; set; }
    public string City { get; set; }
    public string Area { get; set; }
    [Required(ErrorMessage = "Address Details are required.")]
    public string Details { get; set; }
    public bool IsDefault { get; set; }
}

The same thing happens for other view models as well where there are nested view models inside them. One thing I noticed when inspecting the input fields FireBug is that they always have the valid class on them, even when they're not really valid (according to the annotations decorating their properties).

Any thoughts how I can solve this problem?