Apparently, French dissertations are starting to come online at Theses.fr. A quick search discovered one dissertation that was completed last year:
Judith Massengo. "Soteriologie de l'epitre aux hebreux." Ph.D. diss., University of Strasbourg, 2011.
This dissertation is still under preparation. Hopefully, we'll see more dissertations being made available soon on this site.
HT: Roger Pearse