Week over... busy weekend ahead.
Not much stuff apparently done this week even though I feel tired.
The first MTP device now works under Linux!
The iRiver T10, a MP3/OGG player, supports MTP ... And by just adding the USB IDs to libgphoto2/camlibs/ptp2/library.c we made it work.
Interesting is that it does not report the PTP device class, but speaks PTP.
Hub has concerns that we stray off the path of "libgphoto2 is for cameras".... Well, yes. But at least the device works and the user is happy. :)