They do work with Ubuntu 10.10 Maverick. Do not use Fn with F2, instead just press the F2 key by itself to reduce contrast. Press F3 by itself to increase contrast. Some idiot must have thought that the Functions keys are hardly being used, and set the secondary function of the keys to be ALWAYS ON - ie. they are reversed.
So if you want to do an Alt F2 to run a program, you need to do an ALt Fn F2 to do it. If you want to do a F7 you need to do a Fn F7.
If you want your keyboard to act like a normal keyboard you need to go into Bios and change this silly setting. Restart the machine, and press the ESC key followed by the F10 key to get into Bios. Look for Action Key Mode and change the setting to disabled. Save changes and exit f10.
If you want to use the lock symbol key that is on the upper row on the keyboard. On the menu bar, Go to System>Preferences>Keyboard Shortcuts. Scroll down the list and find Lock Screen, it will be set to CTRL+ALT+L, click on the shortcut, it will get cleared, press the lock symbol key, and the shortcut will be changed to Mod4+L, click the close button. Now you can lock your computer just by pressing one key.
You can re-assign the other keys, to start your favourite applications. The key with a wired globe has been set to open your home folder by default. I'm thinking of changing the calculator key to start up LibreOffice Calc spreadsheet instead of the calculator.