EntityFramework 4: Removing items from an ObjectContext without having a reference to the ObjectContext

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.NET4

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Hi all,
I'm having a huge problem deleting records from a database using Entity Framework 4.0...
Let's say I have an Order Object with OrderDetail Objects.

Let's say my Order looks as follows:

public partial class Order
{
    public bool RemoveProductFromOrder(int productId)
    {
        IEnumerable<OrderDetail> details = this.OrderDetails.Where(d => d.ProductId == productId)
        details.ToList().ForEach(d => this.OrderDetails.Remove(d));
        return details.Any();
    }
}

Pretty straightforward I'd say.
So what is the problem? Whenever I remove an OrderDetail this way the only thing that happens is that the reference of the OrderDetail to the Order is set to null. So what happens when I call ObjectContext.SaveChanges()[^]? I get an Exception saying that OrderDetail.OrderId is non-nullable and should have a value.

What is the solution to this? Pretty 'easy'...
I should hook up an event handler to the AssociationChanged Event[^] of Order.OrderDetails and remove the OrderDetail from the ObjectContext[^] manually, like so:

this.OrderDetails.CollectionChanged += (sender, e) =>
{
    if (e.Action == CollectionChangeAction.Remove)
    {
        context.DeleteObject(e.Element);
    }
};

Now the problem is that I don't have a reference to my ObjectContext in every Entity[^]. I could pass a reference to every Entity, but that is not very elegant. It is also disaster waiting to happen since almost every business object would have access to data stuff.
I could hook up the event handler in the same Class where I keep my ObjectContext reference, but that would mean I have to loop through all Orders I fetch from the database(or use the ObjectMaterialized Event[^]) and hook up the event. Plus there is no way to know when a new Order was created (of course I could know, but polling every possible way for object creation and hooking up the event is also a disaster waiting to happen).

Last, I could handle the ObjectContext.SavingChanges Event[^] and check the ObjectStateManager[^] for OrderDetails that do not have an OrderId... But this is also a very nasty solution!

Is there a clean, elegant and maintainable solution to this problem? I couldn't find it and I'm about to pull my hair out (and I've got a lot!) over this problem... Any help is appreciated. Thanks!