About Question enthuware.oce-jpad.v6.2.562 :

[johnlong]

The primary key must be defined on the entity that is the root of the entity hierarchy or on a mapped superclass of the entity hierarchy.

The statement is ambiguous.
In case when mapped superclass is in the middle of entity hierarchy, the primary key should be at the root of entity hierarchy.

[admin]

Where did you read that in the spec??