Hi Kunal,
Thank you for your reply. Jun is correct. I have read this doc
http://help.sap.com/saphelp_nw73ehp1/helpdata/en/54/bf98c82cd84614a85cfda25d70b175/frameset.htm. But not all exceptions or errors can be catched in this way. I want the BPM system to notify the applicant whatever exception happens. That is to say, once a process stops, a notification is sent to the applicant. I think the BPM system shuold be enhanced with this mechanism.
Regards,
Abe