NHibernate query throws exception, when looking by related table - linq

Question

I have pretty simple linq expression:
session.Query<Order>().Where(x => x.States.OrderByDescending(z => z.Date).FirstOrDefault().Name == "2").ToList();
Result: InvalidCastException Unable to cast object of type 'Antlr.Runtime.Tree.CommonTree' to type 'NHibernate.Hql.Ast.ANTLR.Tree.IASTNode'.
Same query with LinqPad works as expected: selects orders, which last state is OnTheWay. How can I circumvent this and get desired result?
Code to try yourself:
class Program
{
static void Main(string[] args)
{
ISessionFactory sessionFactory = Fluently.Configure()
.Database(MsSqlConfiguration.MsSql2008
.ConnectionString(x => x.FromConnectionStringWithKey("defaultConnectionStringForNhibernate")))
.Mappings(m => m.FluentMappings.AddFromAssembly(Assembly.GetEntryAssembly()))
.BuildSessionFactory();
var session = sessionFactory.OpenSession();
var res2 =
session.Query<Order>().Where(x => x.States.OrderByDescending(z => z.Date).FirstOrDefault().Name == "2").ToList();
}
}
public class Order
{
public virtual int Id { get; set; }
public virtual IList<OrderState> States { get; set; }
public virtual string Name { get; set; }
}
public class OrderState
{
public virtual int Id { get; set; }
public virtual string Name { get; set; }
public virtual DateTime Date { get; set; }
public virtual Order Order { get; set; }
}
public class OrderMap : ClassMap<Order>
{
public OrderMap()
{
Id(x => x.Id)
.GeneratedBy.Identity();
HasMany(x => x.States)
.Inverse()
.AsBag()
.KeyColumn("OrderId");
Map(x => x.Name)
.Not.Nullable();
Table("Orders");
}
}
public class OrderStateMap : ClassMap<OrderState>
{
public OrderStateMap()
{
Id(x => x.Id)
.GeneratedBy.Identity();
References(x => x.Order)
.Column("OrderId");
Map(x => x.Name)
.Not.Nullable();
Map(x => x.Date)
.Not.Nullable();
Table("OrderStates");
}
}

Answer 1

After some time research I found solution:
var res = (from i in session.Query<Order>()
where ((from s in i.States
orderby s.Date descending
select s.Name).First()) == "2"
select i).ToList();