Session.merge() doesn't work on @Entity with mulitiple @Id, one of which is a @OneToMany. The same works fine if @EmbeddedId is used.

Attached maven project for reproducing the issue.

• Run com.bug.Service
• Parent1-->Child1 uses @EmbeddedId. It is working fine.
• The same when modeled using @Id (Parent2-->Child2) doesn't work.