Migrate from EJB 2 Entity Bean to EJB3

I am having some entity beans created in EJB 2.0 and now I need to migrate to EJB 3.x, but I've studied that use of entity beans are changed in EJB 3.x and they are using JPA instead.

Where can I find solution to actuate my beans to be comfortable with EJB 3.x?

For example from following resources available online:

• http://www.datadisk.co.uk/html_docs/ejb/ejb3_migration.htm
• http://www.oracle.com/technetwork/middleware/ias/oc4j-twp-ejb3-migration-1013-133021.pdf

or following printed books:

• Pro JPA 2 Mastering the Java Persistence API (p. 457-466)
• EJB3 in Action (p. 513-528)