You do not need to build whole product but you will need to make few changes to the files such as persistance.xml which are inside jar an wars.
There are already tutorials available in JBPM forum which wil be helful to you.
Thank you for your response. What I need then is an automated way to pull down the jBPM jars, unjar them, modify the xml, rejar them and then let my current maven feature builder create the offline repo for my JBoss Fuse container. Anyone have reasonbly straight forward directions on doing that with either Maven or Ant? Those are the tools I'm given and everything needs to be automated so it can "rebuild" the system and send a fully operational zip file to our production team so they can just delete the currently running folder and unzip the new and restart it.