I think it is this exception that is playing havoc. This is coming probably because, i tried to run the RuleGroup through the jBPM web console: just did it to see what would happen if I run a rule group. Whenver this exception does not come, the rules are running, when the exception is raised the rules are not running. So i start with installation of BRMS/jBPM again. Let me see if this gets resolved with the new installation. Meanwhile if anyone got this exception and resolved it without having to start from the re-installation, please let me know: it would help a lot. I feel a small mistake like this should not bring the whole server down once for all. Anyway I am not sure of all this, I am a newbie to BPM/BRMS integration with JBoss.