the versions we are using are jbpm3.2.8 and jboss5.1.0
Hi there.. you want to create process instances using classes? or process definitions using classes?
For jBPM 3, you can read the book: https://www.packtpub.com/jboss-business-process-management-jbpm-developer-guide/book
that explains how to use the APIs to interact with your processes.
jBPM 3 is quite old these days and most of the questions that we are answering here are for jBPM5.