Someone ... ??
I think it's some kind of bug causing the @Id to do 'it's thing' first, creating a blob field (storing an object reference) with a pri key. Then the @ManyToOne responsible for laying the relation and make the field the type of the referencing key, but it doesn't do that because the field is already present.
I installed the RC4 but that didn't change anything.
It is a bug ?
this is not supported yet