Looking at the jinput pages, it looks like java.net had an issue at some point. I don't know what it was. The error you are seeing did happen in some older distributions. The distribution zip should have a time stamp of the 9th of Jan 2008. I've just checked it on two of my ubuntu servers and it's playing nicely.
The other keyboards can be ignored if you want, mine are things like a sleep button, a power button (or two). I think they might be for when you have those buttons on a USB keyboard, but I've never tried pressing them as I don't want to shut the machine done

The controller text test reveals the extras for one of my machines as
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| Sleep Button (CM) Type: Keyboard Component Count: 1 Component 0: Sleep Identifier: Sleep ComponentType: Absolute Digital --------------------------------- Power Button (CM) Type: Keyboard Component Count: 1 Component 0: Unknown Identifier: Unknown ComponentType: Absolute Digital --------------------------------- Power Button (FF) Type: Keyboard Component Count: 1 Component 0: Unknown Identifier: Unknown ComponentType: Absolute Digital |
HTH
Endolf