This likely means the objects you are attaching have not been instrumented by AOP.
Thanks for the response. I had the same hunch too. I searched info about it and realized that I had to put pojocache-aop.xml in the classpath, which I did (put pojocache-aop.xml into WEB-INF/classes as its a web application). But still keep getting the exact same error. Is there anything else that need to be done to instrument the class at run/load time. Can you please give me some pointers.