Comment 17 for bug 259244

Hm, Logitech keyboards are naughty. Your's identifies exactly like the Logitech Wave Cordless, but apparently has entirely different scancodes.

Can you please download the two attachments that I'll do, and install them with

  sudo cp 95-keymap.rules /lib/udev/rules.d/
  sudo cp logitech-wave-cordless /lib/udev/keymaps

then detach/reattach the keyboard and see if the "unknown scancode" errors disappeared? Please also check with /lib/udev/keymap -i <device> (find out the <device> with "findkeyboards") that the two keys now really produce "zoomin" and "zoomout".

Thanks!