Hi,<br><br>Using version 3.0.6 of jboss rules, while retracting an object, I get the following:<br><br>&nbsp;java.lang.NullPointerException<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.beta.InstanceEqualConstrRightMemory.remove(Unknown Source)<br>
&nbsp;&nbsp;&nbsp; at org.drools.reteoo.BetaMemory.remove
(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.NotNode.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.ObjectSource.propagateRetractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.RightInputAdapterNode.retractTuple

(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.TupleSource.propagateRetractTuple(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.NotNode.retractTuple(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.TupleSource.propagateRetractTuple

(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.JoinNode.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.ObjectSource.propagateRetractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.ObjectTypeNode.retractObject
(Unknown Source)
<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.Rete.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.ReteooRuleBase.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.reteoo.ReteooWorkingMemory.doRetract(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at 
org.drools.common.AbstractWorkingMemory.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at org.drools.common.AbstractWorkingMemory.retractObject(Unknown Source)<br>&nbsp;&nbsp;&nbsp; at ascc.rules.AbstractRulesCoordinator.statusChanged(AbstractRulesCoordinator.java

:354)<br>&nbsp;&nbsp;&nbsp; at ascc.rules.AbstractRulesCoordinator$1.statusChanged(AbstractRulesCoordinator.java:111)<br>&nbsp;&nbsp;&nbsp; at ascc.status.BaseStatusBoard.notifyChange(BaseStatusBoard.java:211)<br>&nbsp;&nbsp;&nbsp; at ascc.status.BaseStatusBoard.notifyChange

(BaseStatusBoard.java:191)<br>&nbsp;&nbsp;&nbsp; at ascc.status.DefaultParkingStatusBoard.empty(DefaultParkingStatusBoard.java:318)<br>&nbsp;&nbsp;&nbsp; at ascc.spotting.DefaultSpottingCoordinator.computeInitialSpot(DefaultSpottingCoordinator.java:578)
<br>&nbsp;&nbsp;&nbsp; at ascc.spotting.DefaultSpottingCoordinator.statusCreated(DefaultSpottingCoordinator.java:827)<br>&nbsp;&nbsp;&nbsp; at ascc.status.BaseStatusBoard.notifyCreate(BaseStatusBoard.java:100)<br>&nbsp;&nbsp;&nbsp; at ascc.status.BaseStatusBoard.notifyCreate

(BaseStatusBoard.java:80)<br>&nbsp;&nbsp;&nbsp; at ascc.status.DefaultAirPlanStatusBoard.missionAssignmentComplete(DefaultAirPlanStatusBoard.java:479)<br>&nbsp;&nbsp;&nbsp; at ascc.missionassignment.Rule_6___Complete_mission_assignment_for_event_0.consequence

(Rule_6___Complete_mission_assignment_for_event_0.java:36)<br>&nbsp;&nbsp;&nbsp; at ascc.missionassignment.Rule_6___Complete_mission_assignment_for_event_0ConsequenceInvoker.evaluate(Rule_6___Complete_mission_assignment_for_event_0ConsequenceInvoker.java:24)
<br>&nbsp;&nbsp;&nbsp; ... 7 more<br><br>Is there something I could be doing wrong?&nbsp; Is this a known bug?<br><br>Thanks,<br>-Chris<br>