hope you got the reply already(Questionposted on june/06).
its failing because there is no @Id annotation for atleast one field.
because every entity must have a primary key.
it can be either simple or composite
I have the same problem (using EJB 3.0 RC9), but after a series of tests I found the source: I defined my identifier within an abstract superclass, and the EJB 3 deployer didn't recognize it, leading to the throwing of the exception mentioned in the previous post.
Is this a bug (which must be reported) or is a feature of the J2EE 5 spec?