Play Framework 2.0 Beta & integration into Typesafe Stack(groups.google.com)

    class Order(val customerName)
        @OneToMany
        Set<OrderItem> items;
    class Item(itemDescription)
        @OneToMany
        Set<OrderItem> orders;
    class OrderItem(val quantity)
        @Id
        @PrimaryJoinColumn
        @ManyToOne
        Order order;
        @Id
        @PrimaryJoinColumn
        @ManyToOne
        Item item;

    OrderItem oi;
    oi.item = bananas;
    order.items.add(oi);
    order.save(); // This saves oi, but with a null value for order_id
    oi.order = order; //This seems redundant, but the save is wrong without it.