This is related to an issue in the generated scaffold of the TicketMonster model: JDF-391.

The generated Faces scaffold does not treat immutable properties and collections of immutable properties differently. Differential treatment is required since immutable properties lack setters and hence instances of them need to be created via the specialized constructors that exist for the immutable entities.

Updates of immutable properties will require deletion of existing immutable instances followed by creation of new ones.