Michael,
Actually, it's not exif data i want to change. It's file attributes like "title", "theme" or "commentary" (deutsch: Titel, Thema, Kommentare)
in fact, IrfanView does have this capability (you can read and/or embed standard IPTC tags) so Jens' suggestion was pretty good IMHO. I am just not sure, if it's standard feature or you have to install some plugin to enable it. It's free for non commercial use.
Bedo.
