Hi Rama.
Maybe having a look at Activiti Cycle and the Signavio Core Components (and the Activiti Modeler) could be interessting for you in this case?
See e.g. http://www.bpm-guide.de/2011/03/22/the-bpm-roundtrip-with-activiti-cycle/. This is not tied to the Activiti Engine and could be integrated with jBPM 5 as well. Actually a big pilot customer uses this approach with jBPM 3. And jBPM 4 based a web modeler on the same code base for the modeler (actually the Signavio Core Components are the successor of Oryx, which is now an officially abandonned project).
Cheers
Bernd