Does this mean the translator still has the copyright on the translation but declares not using this copyright ?
As far as I understand, yes.
Ok, very good. Does that mean generally that personal copyright of a document is not compatible with GPL ? Or is it only a FSF request ?
I am currently working on the maintainance of a GPLed user manual (not FSF related) and we (the dev team and I) have had questions recently about the role of copyright in such a licenced document.
Are there cases where copyright and GPL can contradict each other ? Or is this FSF request only to make sure that the copyright owner will never change the licence to a non GPL version (which could be done I suppose by claiming copyrights) ?
Jean-Christophe Helary