[rules-users] question on adding manual workitem within flow editor

Hi, I'm a newbie of Drools and I just met a problem when learning Drools Flow according to Drools online documents. I create a workitem, Notification, exactly according to Chapter 8 in Drools Flow Doc. I create MyWorkDefinitions.conf and drools.rulebase.conf, and then put them in classpath. Also, I create one image to be used by the item. However, this new workitem is not found in RuleFlow Editor. I'm not sure if something else is needed. Can you guys please guide me to adding new workitem and dragging/drawing it in RuleFlow Editor? FYI. Though the RuleFlow editor cannot work with the new workitem, the XML style works. I mean, I could manually change the XML of .rf file to use the new workitem. The work environment is JDK5, Drools5, Eclipse 3.4.5 and GEF 3.5. The two conf files are also attached. <<drools.rulebase.conf>> <<MyWorkDefinitions.conf>> Thanks, Paul