[rules-users] How to define an Enumeration when using "Guided Editor" in Eclipse?

Hi all Probably a simple question, but I did not find any hint on this topic. I am using drools 5.0 in eclipse. There I started to write "business rules" with the "guided editor". Now I like to introduce some enumeration for some attributes in my model. In the web based version "Guvnor" is this no big deal, there you have the option to add new "enumerations". But how can you achieve the same thing in eclipse? I studied the "package" file syntax, but there I found no such option (or it is not documented). Any suggestions and hints? Many thanks for your help in advance. regards Mark