It seems that Jboss cache won't allow a same object to be cached by 2 different cache ?? java.lang.RuntimeException: InternalDelegate.incrementRefCount(): null aopInstance for fqn: /one/two at org.jboss.cache.aop.InternalDelegate.incrementRefCount(InternalDelegate.java:96) at org.jboss.cache.aop.ObjectGraphHandler.incrementRefCount(ObjectGraphHandler.java:212) at org.jboss.cache.aop.ObjectGraphHandler.setupRefCounting(ObjectGraphHandler.java:192) at org.jboss.cache.aop.ObjectGraphHandler.objectGraphPut(ObjectGraphHandler.java:88) at org.jboss.cache.aop.TreeCacheAopDelegate._putObject(TreeCacheAopDelegate.java:201) at org.jboss.cache.aop.PojoCache._putObject(PojoCache.java:739) at org.jboss.cache.aop.PojoCache.putObject(PojoCache.java:465) at example.TestCircularRef.main(TestCircularRef.java:44) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4050441#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...