OK we found the issue. In the first case (pure Groovy), the annotations are placed on the fields (always the case for Groovy) and metaClass is indeed a transient field thus ignored. In the second case I suspect your java class has it's annotations on getters. So JPA expect to find annotations on getters and process getters of the Groovy class. Hence it picks getMetaClass, and incidentally does not read your annotations in Groovy (field instead of property). The solution is to use field annotations for your superclass in Java. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4113140#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...