[rules-users] java.lang.RuntimeException: Unexpected global

Hi, What is the actual reason for this error? Why cant drools give some better explaination of this problem when the exception is thrown. Here is the snippet of my code: workingMemory.setGlobal("validationErrorHierarchy", validationErrorHierarchy); //workingMemory is StatefulKnowledgeSession I am using the following variable in dslr: global com.model.ValidationErrorHierarchy validationErrorHierarchy; thanks saleem