What version of JBoss Cache is this? To restate what I think I've heard: You put an aspectized pojo in the cache. The pojo has a field of type List. A Serializable object (non-aspectized) is placed in the List. That object has a ref to 2 aspectized pojos, but those pojos were never placed in the cache. That sounds fine. PojoCache should treat the non-aspectized object as opaque, so the fact that the other 2 pojos were aspectized shouldn't matter. Particularly if the cache never saw the 2 pojos directly. Do the last two pojos have a reference to anything that was put in the cache? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3982488#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...