olivier.chirossel(a)sfr.com wrote: Please test the latest commit of overlays/rwm.c (should apply fine to 2.4.23) and report. It fixes the double free. With respect to your problem description, "lastmod off" means that the backend will not *generate* modification-related operational attributes; however they are proxied. Moreover, you can't strip them off with mapping unless the remapping is part of a replication process (i.e. the backend contains syncrepl or "updatedn" is set and the operation is performed with that identity). p.