I'm getting the exception:
java.lang.IllegalStateException: INSERTING AN ALREADY EXISTING BEAN, ID = ????

This happens I believe due to the fact that in my ejbCreate() method, I create other objects (actually leaf
objects that depend on the current object). So in my
ejbCreate() method, I do some work, call super.ejbCreate()
then create payment_item records that depend on the current payment, then return the key returned from the
super.ejbCreate().