I'm trying to do a simple example of loading enums programmatically pretty much following the user guide example. I'm on Drools and BRMS 4.0.5, Java 1.6 running under Jboss. I'm trying to define this 'data enumeration/drop down list' package com.alcatel_lucent.utils; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; public class DataEnumSource { public Map<String, List<String>> loadData(){ Map<String, List<String>> map = new HashMap<String,List<String>>(); List<String> l = new ArrayList<String>(); l.add("foo"); l.add("boo"); map.put("AvpSubscriptionId.subscriptionIdType", l); l = new ArrayList<String>(); l.add("apple"); l.add("bannana"); map.put("AvpServiceContext.serviceContextId",l); return map; } } The jar containing the DataEnumSource has been defined as a model within BRMS. Here's what I put in the 'Data enumeration' text window =(new DataEnumSource()).loadData() When validating the Data enumeration from BRMS, I get the following error: Unable to load enumeration data. unable to resolve class: DataEnumSource Error type: org.mvel.CompileException Any insight as to what might be the problem?