Does anyone have any techniques for profiling what's happening within JBoss 3.0 for EJBs?

I notice that the CPU gets pretty loaded when I run some stress tests on my EJBs, but I haven't come up with a sophisticates way to determine what's going on.

I have a feeling that I may need to do some redesign, but without information I would just be flying seat of the pants.

Would appreciate any ideas, hints, links, etc.