@lazarv or @robesz

Can I get some guidance? I have this structure

class User {
    Id: int,
    Contact: Custom.Namespace.Contact
}

and I'm trying to do something like

context.Users.attachOrGet({Id:1}).Contact.FirstName = "Sam";
context.saveChanges();

Though I get an exception because Contact is undefined. Is it possible to do deep updates? If so can you give an example or point me to some documentation?