If configure(String) has been called on Ejb3Configuration before adding more @Entity-annotated classes with addAnnotatedClass, the @PostLoad callbacks of the classes added with addAnnotatedClass do not work. If the class is added with addAnnotatedClass before configure(String) is called, the callbacks work as expected. The documentation at http://www.hibernate.org/hib_docs/entitymanager/reference/en/html/configuration.html shows a listing where configure(String) is called before addAnnotatedClass, which in my more minimal test case results in the callbacks on the added class not being called. The attached test case extracts a directory cbtest with the following files in it: test.xml, test.sh, test/Something.java and test/Test.java. test.sh compiled and runs the test, provided that necessary jars have been copied to cbtest. The necessary jars are from Hibernate Core 3.2.5, Hibernate Annotations 3.3.0 and Hibernate EntityManager 3.3.1, except for hsqldb.jar, which is needed because the configuration in test.xml expects Hsqldb.