In our case we have implemented a bridge btetween jbpm and jboss esb which does exactly this. We are able to define technical or business fault transiations which will/can be taken based upon the outcome of the service.We did create a dedicated 'service router' for this which reads the Ãnstructions'from the jms gateway and afterwards informs jbpm of the outcome.
We did this in another project as well, but there we changed quite a lot in the integration (almost a complete rewrite). tried to avoid that in the current project ;-)
But what would be really interessting: How do you define exactly, what is a technical and what a business fault?