Actually, here is a nice example of another way of doing this. JBoss SEAM uses jBPM for process flow. In the example in the documentation, they have a TODO list. You could use something like this along with your business logic to generate either rules or a process definition dynamically.
http://docs.jboss.com/seam/reference/en/html/tutorial.html#todo
Kevin
Thanks for all the info, we're looking at the references and are digesting it all :).