NHibernate vs Entity Framework 5 auto connecting entities - nhibernate

Question

Recently I've come back to the question NHibernate vs EF5 for the Enterprise Application.
I know many important differences, but this one is the most suprising for me.
Consider two classic entities, Customer and Order (1:n):
public class Customer
{
public Customer()
{
Orders = new HashSet<Order>();
}
public virtual Guid Id { get; set; }
public virtual string Name { get; set; }
**public virtual ICollection<Order> Orders { get; set; }**
}
public class Order
{
public virtual Guid Id { get; set; }
public virtual Guid CustomerId { get; set; }
public virtual string Number { get; set; }
public virtual DateTime Date { get; set; }
**public virtual Customer Customer { get; set; }**
}
For both NHibernate and EF5 there are two-way mappings.
Code snippets for loading all customers AND all Orders in context of DbContext and Session for EF5 and NHibernate accordingly:
using (TestOrmForDalDbEntities context = new TestOrmForDalDbEntities())
{
context.Configuration.ProxyCreationEnabled = false;
IQueryable<Customer> customers = context.Customers;
customers.Load();
IQueryable<Order> orders = context.Orders;
orders.Load();
}
using (ISession session = _sessionFactory.OpenSession())
{
var customers = session.Query<Customer>().ToList();
var orders = session.Query<Order>().ToList();
}
The result is:
EF5: Each Customer has a collection of appropriate Orders (EF5 automatically connect them)
NHibernate: None of Customers has a collection of appropriate Orders. Even though each Order HAS link to an appropriate Customer.
The question is: is it an NHibernate idea not to connect in such way or it's me who doesn't know how to configure NHibernate?
P.S. Mappings for NHibernate:
public class CustomerMap : ClassMap<Customer>
{
public CustomerMap()
{
Id(x => x.Id).UnsavedValue(Guid.Empty).GeneratedBy.Guid();
Map(x => x.Name);
HasMany(x => x.Orders).Cascade.All();
}
}
public OrderMap()
{
Id(x => x.Id).UnsavedValue(Guid.Empty).GeneratedBy.Guid();
Map(x => x.Number);
Map(x => x.Date);
Map(x => x.CustomerId);
References(x => x.Customer);
}

Answer 1

The relation from Customers to Orders (HasMany) should be Inverse, meaning, it's the Order endpoint that has the foreign key to the Customer.