We typically don't include EclipseLink and other persistence provider jars.   This is a placeholder that the user could copy EclipseLink jars into (and update module.xml).  The idea being to help them get started with using any standard persistence provider.  I could raise a discussion about this on the wf8 design forums to get input on this.  "This" being, trying to make it easier to work with WF8 and different (standard) persistence providers.  The other part to discuss, might be whether we want to have partially filled in static modules that don't work until more jars are added.