POST http://localhost:4007/persons.xml HTTP/1.1
Content-Type: application/x-www-form-urlencoded

basic[last_name]=Smith&basic[first_name]=John

public class Person
    {
        public class Basic
        {
            string first_name;
            string last_name;
            string middle_name;
        }

        public Person()
        {
            basic = new Basic();
        }

        public Basic basic;
    }

// POST api/product 
public HttpResponseMessage Post(Product product)
{
    if (ModelState.IsValid)
    {
        // this will set the ID for instance...
        product = repository.AddProduct(product);     
 
        var response = Request.CreateResponse(
                             HttpStatusCode.Created, product);
 
        string uri = Url.Link("DefaultApi", new {id = product.Id});
        response.Headers.Location = new Uri(uri);
        return response;
    }
    else
    {
        return Request.CreateResponse(HttpStatusCode.BadRequest);
    }
}