I am using Emacs 23 under Mac OS X. When I open certain files I get the following error when I try to save them:
Warning: ns-convert-utf8-nfd-to-nfc unsupported under GNUstep. insert-file-contents: Wrong type argument: char-or-string-p, nil
Sometimes the opening of new files fails with the same message. When I retry opening them, it works. I have no idea how to fix this. In general unicode works fine.