How to change the primary key for a EntityData derived class default string Id property to an int property?

I recently started to learn about Azure Mobile Services, I followed this tutorial about it and the classes for my model are required to inherit from the EntityData class.

From the EntityData source code, an Id property is already defined to act as a primary key, but it is defined as string which doesn't work for my Model that uses int.

My class looks like this:

public partial class Role : EntityData
{
    public Role()
    {
        this.Users = new HashSet<User>();
    }
    [Key]
    public int RoleId { get; set; }
    public string Title { get; set; }

    public virtual ICollection<User> Users { get; set; }
}

If I try to use this class, I get an error message saying an Id property is already defined.

Is there a way to define a different property as a primary key? In case this change is not possible, is there a way to use this string Id property as an incremental primary key?