[rules-users] How implement custom editor for Drools Flow work definitions?

Hi, I'm trying to implement a custom editor for my own work definitions in Drools Flow but run into classloading issues when I try to start the custom editor from Eclipse. I have tried various ways of building and packaging my class but all result in NoClassDefFoundError, LinkageError, ClassCastException etc. Does anyone know what's the trick to successfully making and using an own implementation of org.drools.process.core.WorkEditor? Any pointers or example code would be much appreciated. Thanks, Mattias Nilsson