It also means the business that Hibernate does where it converts entity class com.foo.some.really.deep.package.tree.MyEntity to an Fqn via Fqn.fromString("/com/foo/some/really/deep/package/tree/MyEntity") can be simplified to a more efficient Fqn.fromString("com.foo.some.really.deep.package.tree.MyEntity"). That deep-tree style was added sometime a long while ago when there was some locking contention on parent nodes. The only reason I hadn't gotten rid of it was this optimistic child-map copy thing. :) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4095743#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...