Hello, I am getting the following intermittent error from drools 5.0.1 when removing a knowledge package from a knowledge base: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory I iterate over knowledgeBase.getKnowledgePackages() and the error occurs, but only occasionally. The full trace is as follows: java.lang.ClassCastException: org.drools.reteoo.BetaMemory cannot be cast to org.drools.reteoo.RuleTerminalNode$TerminalNodeMemory at org.drools.reteoo.RuleTerminalNode.doRemove(RuleTerminalNode.java:357) at org.drools.common.BaseNode.remove(BaseNode.java:95) at org.drools.reteoo.ReteooBuilder.removeRule(ReteooBuilder.java:237) at org.drools.reteoo.ReteooRuleBase.removeRule(ReteooRuleBase.java:366) at org.drools.common.AbstractRuleBase.removeRule(AbstractRuleBase.java:712) at org.drools.common.AbstractRuleBase.removePackage(AbstractRuleBase.java:640) at org.drools.impl.KnowledgeBaseImpl.removeKnowledgePackage(KnowledgeBaseImpl.j ava:166) Any ideas why this would potentially happen? Cheerio, Nic Nicholas Hemley Senior Developer Sidonis | Powering a New Generation of Service Assurance