ERROR in Workflow

Hi,

I am getting this error when executing the WF

I am developing in TWE 2.1.1 on Sourcing 9.0.15

java.lang.NullPointerException: while trying to invoke the method com.sap.odp.workflow.xpdl.FinishMode.getManual() of a null object returned from com.sap.odp.workflow.xpdl.Activity.getFinishMode()

at com.sap.odp.workflow.engine.handlers.PhaseChangeInstantiationRequestHandler.processActivity(PhaseChangeInstantiationRequestHandler.java:352)

Any pointers will be appriciated.