Thanks you very much. Now it works. This tool should be included in the Dreambox Distribution.

Have a nice Day.

Did you receive a clean picture? I tried it with

root@dm7025:/media/hdd# fbshot -d /dev/fb/0 test.png
Framebuffer /dev/fb/0 is 1658880 bytes.
Grabbing 720x576 ...
done.
Writing test.png ...done.

but the the On Screen Menu is only visible in the background behind some transparent grey blocks.