[rules-users] NPE after rule consequence executes

[Scott Reed]

Running Drools 4.0.3, on Win 2k sp4, JDK 1.6.0_03.

I am getting this exception after the debugger shows execution has gone 
past the end of the rule. The exception is occurring in 
ReteTuple.get(Descriptor). I believe the descriptor argument is null. 
Can anyone suggest why this might be happening and what I can do to 
avoid it?
Thanks,
  Scott

java.lang.NullPointerException
    at org.drools.reteoo.ReteTuple.get(ReteTuple.java:97)
    at 
org.fp.findata.Rule_2MS__Calculate_now_scheduled_or_periodic_transaction_0ConsequenceInvoker.evaluate(Rule_2MS__Calculate_now_scheduled_or_periodic_transaction_0ConsequenceInvoker.java:19)
    at 
org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:550)
    at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:514)
    at 
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:471)
    at 
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:433)
    at 
org.fp.rules.RuleEngineManager$RunTask.run(RuleEngineManager.java:225)
org.drools.spi.ConsequenceException: java.lang.NullPointerException
    at 
org.drools.base.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:14)
    at 
org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:554)
    at org.drools.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:514)
    at 
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:471)
    at 
org.drools.common.AbstractWorkingMemory.fireAllRules(AbstractWorkingMemory.java:433)
    at 
org.fp.rules.RuleEngineManager$RunTask.run(RuleEngineManager.java:225)
Caused by: java.lang.NullPointerException
    at org.drools.reteoo.ReteTuple.get(ReteTuple.java:97)
    at 
org.fp.findata.Rule_2MS__Calculate_now_scheduled_or_periodic_transaction_0ConsequenceInvoker.evaluate(Rule_2MS__Calculate_now_scheduled_or_periodic_transaction_0ConsequenceInvoker.java:19)
    at 
org.drools.common.DefaultAgenda.fireActivation(DefaultAgenda.java:550)
    ... 4 more