Refer to forum topic http://www.avaje.org/topic-33.html
Beans annotated to the JPA spec will not work with Ebean. Specifically for beans with more than 1 relationship to another bean, and annotated as per the JPA spec will have an issue.
The example is User related to Bugs by User.loggedBugs and User.assignedBugs. In JPA examples mappedBy attribute is used and currently Ebean uses an explicit join (via @JoinColumn etc) and guesses the mappedBy attribute dynamically.
The net net is that some annotated beans similar to examples in the JPA spec may not work with Ebean currently.
I have fixed this and will include this in the next version.