In my opinion the most sutiable node in BPMN2 for state node from jBPM v4 would be catch intermediateSignalEvent which will wait for an external signal, that should be done either through process instance or session that contains the process instance.
Exanle of BPMN2 file you can find here and sample code that operates on this can be found in testIntermediateCatchEventSignal() method here
HTH