Hi,

I would like to find a solution working with the IDE. If that should
not be possible I will look for alternative ways, but for now I will
try to do it that way.

Theoretically you don't have to worry anymore about the libraries and
the classpath when you are using Netbeans - theoretically! That is why
at this moment I don't think that it is an issue of that. Also the
fact that the error does not talk about a Hibernate problem, but a
Toplink problem. Here is a part of it:

The following providers:
oracle.toplink.essentials.PersistenceProvider
oracle.toplink.essentials.ejb.cmp3.EntityManagerFactoryProvider
Returned null to createEntityManagerFactory.

That is why I am still convinced that the problem is that I was not
able to switch completely from Toplink to Hibernate just by changing
the persistence provider in persistence.xml.

Thank you!

Best regards,

Tilo