Is the orm.xml in drools-persistence-jpa-5.1.0.M2.jar still correct? I'm getting the exception: Error in named query: ProcessInstancesWaitingForEvent org.hibernate.QueryException: cannot dereference scalar collection element: name [select processInstanceInfo.processInstanceId from org.drools.persistence.processinstance.ProcessInstanceInfo processInstanceInfo where :type in (processInstanceInfo.eventTypes.name)] And the query in orm.xml in fact doesn't seem to reflect the latest changes in ProcessInstanceInfo.java (?) --- org.drools.persistence.processinstance.ProcessInstanceInfo.java // @OneToMany(cascade = {CascadeType.PERSIST, CascadeType.MERGE}) // @JoinColumn(name = "processInstanceId") // private Set<EventType> eventTypes = new HashSet<EventType>(); private @CollectionOfElements @JoinTable(name = "EventTypes", joinColumns = @JoinColumn(name = "InstanceId")) Set<String> eventTypes = new HashSet<String>(); --- orm.xml: <query> select processInstanceInfo.processInstanceId from ProcessInstanceInfo processInstanceInfo where :type in (processInstanceInfo.eventTypes.name) </query> (Removing the .name in the query didn't help...) -- View this message in context: http://drools-java-rules-engine.46999.n3.nabble.com/orm-xml-for-5-1-0-M2-... Sent from the Drools - User mailing list archive at Nabble.com.