This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
First, JPA is not beans. JPA is a specification about data persistence. There are no beans, but what is called "Entities". Entites are accessed via an entity manager. It can be used on a EJB3 container or even in J2SE. Again, JPA is a specification. It is implemented by a few JPA containers, like Hibernate or Toplink.