I'd probably look to an external scheduling package. Chron comes with unix systems, but there are many sophisticated commercial products. If you want to roll your own, could you run another JVM outside the J2EE container with something as simple as Timer?
A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi