We are seeing this exception when trying to complete flows in wait state. This happens after we deploy a newer release of our application. Context: 1. we start several process that go to wait state 2. we make bug fixes to our application and deploy a new version 3. we try to resume the existing flows that are in wait state. 4. we get this exceptions when trying to load existing session NOTE: drools version is the same so I don't think this is a serialization incompatibility issue. Exception: Caused by: java.lang.reflect.InvocationTargetException at sun.reflect.GeneratedConstructorAccessor622.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27) at java.lang.reflect.Constructor.newInstance(Constructor.java:513) at org.drools.persistence.jpa.impl.KnowledgeStoreServiceImpl.buildCommanService(KnowledgeStoreServiceImpl.java:95) ... 202 more Caused by: java.lang.RuntimeException: Unable to load session snapshot at org.drools.persistence.session.JPASessionMarshallingHelper.loadSnapshot(JPASessionMarshallingHelper.java:96) at org.drools.persistence.session.SingleSessionCommandService.initKsession(SingleSessionCommandService.java:202) at org.drools.persistence.session.SingleSessionCommandService.(SingleSessionCommandService.java:165) ... 206 more Caused by: java.lang.ClassCastException: org.drools.reteoo.EvalConditionNode cannot be cast to org.drools.reteoo.RightTupleSink at org.drools.marshalling.impl.InputMarshaller.readRightTuple(InputMarshaller.java:401) at org.drools.marshalling.impl.InputMarshaller.readRightTuples(InputMarshaller.java:391) at org.drools.marshalling.impl.InputMarshaller.readFactHandles(InputMarshaller.java:326) at org.drools.marshalling.impl.InputMarshaller.readSession(InputMarshaller.java:205) at org.drools.marshalling.impl.DefaultMarshaller.unmarshall(DefaultMarshaller.java:91) at org.drools.persistence.session.JPASessionMarshallingHelper.loadSnapshot(JPASessionMarshallingHelper.java:91) ... 208 more Thanks, Nick -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/EvalConditionNode-can... Sent from the Drools - User mailing list archive at Nabble.com.