Currently I (together with a friend) am working on jBPM and Drools platform that is based on JBoss AS 7 which means JBoss Modules and JBoss OSGi. Currently we are at concept study phase that is almost over and implementation has started. We plan to have PoC version of it in around one month.
If you are interested I can provide you with an abstract introduction to the project and of course we always welcome contributors - project is open source :)
Cheers