As you now appreciate, a substantial part of the implementation effort for CMP Entity beans is simply completing the deployment descriptor correctly.
This will always involve completing the entity element of the deployment descriptor, either manually or using a GUI tool such as deploytool. If the CMP Entity has container-managed relationships, these too must be specified under the relationships element of the deployment descriptor.
To remind you, the structure of the deployment descriptor is as follows:
<!ELEMENT ejb-jar (description?, display-name?, small-icon?, large-icon?, enterprise-beans, relationships?, assembly-descriptor?, ejb-client-jar?)>
Here you can see the relationships element, ...