no problem.
I haven't spotted any....however if you study the documentation u'll understand how to use jbpm from the api http://docs.jboss.org/jbpm/v5.0/userguide/ch03.html , in order to call these u'll have to include the essential runtime jars of jbpm.
If you choose to use the REST web services available hit http://localhost:8080/gwt-console-server/ and http://localhost:8080/gwt-console-server/rs/server/resources , you will find there some of the web services available and what kind of http request to use i.e. GET/POST
To understand how they are being called use the jbpm-console and look at the log to see the calls at the gwt-console-server as you look at the processes and tasks etc.
(also check out this thread regarding rest http://community.jboss.org/thread/149568 )