in a extended scanrio (a workbench project that include as dependency another project) if an enumeration is defined in base class, in the extended class ( if the dataobject is correctly imported) the drop-down list not appears in workbench.

in the base class the class the drop-down list correctly appears

the issue was discussed here
https://groups.google.com/forum/#!topic/drools-usage/jFVeSZZWi54