Disable XPS Studio 16 Sleep Function Key?

I'd like to know if there's a way to disable the sleep key on my XPS Studio 16 keyboard? Pressing the Fn + F1 key combination activates sleep mode, without any further prompt to do so. I have an application in which several shortcuts are mapped to keys close by, and I can't risk accidentally putting the pc to sleep with the slip of a finger.

Please note that I've already tried the Control Panel\Power Options\System Settings "When I press the sleep button" option. It's set to "Do Nothing" and yet, Fn + F1 still put the computer to sleep. I've also looked int he BIOS (A9) and found no option there to change the setting. 

What I'm looking for is a utility or a setting to either disable that (or all) function keys or change what it does. A registry hack would also suffice. 

Anyone?