I'm taking a wild guess here, but you're defining 2 entities that have a one-to-one relationship and are joined by their primary keys, so have you implemented those semantics in your java classes? For example, what happens if I call setFieldId on Field, does it's associated FieldAccess instance have it's fieldId kept in sync? What about vice versa? And for the getters? Given the life-cycles of each type, can you get by with a single fieldId property in just one of the classes? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4142507#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...