Hello,
He is a core-twisted developer and a very experienced Python developer with a passionate belief in good testing. He also regularly comments the issue tracker. Twisted run their test framework against python-trunk, so he often reports compatibility issues they discover.
I'd like to second Michael's opinion about Jean-Paul's competence, especially on network and system matters.
I would be very happy to 'mentor' him, but don't think I qualify as I wouldn't be able to check C patches. He knows the Python workflow well enough though.
I can mentor him if necessary.
Regards
Antoine.