Github user hartig commented on the issue:
https://github.com/apache/jena/pull/299
I finally have implemented a Turtle* parser that hooks into Jena's RIOT
parser framework and uses the `Node_Triple` class that @afs had added to Jena
in PR #327. Find the code at https://github.com/RDFstar/RDFstarTools
Thanks again all for your efforts! I think we now can close this PR here.---
