Karsten,
A few things are going on. Currently, we are trying to stabilize the AS 7.1 codebase, which means more attention is being spent elsewhere at the moment. A few people have volunteered to work on the EclipseLink integration but the results of their work has not been shared yet.
I heard an update privately, a few weeks ago, which I will quote. "EclipseLink can't find the classes inside the Jar due to the null stream returned from the vfs: URL."
Are you (or anyone else), interested in helping with the integration?
Scott