Nyko Kama brand nunchuck not working with WiiChuck.h

I needed a nunchuk in a hurry so ran out to Target and bought a "Nyko Kama" wired nunchuk. The Nintendo brand nunchuk that came with my Wii works fine with WiiChuck.h, and this Nyko Kama nuncuk works fine with the Wii, so I figured it would work with the Arduino and WiiChuck.h. However, when I connect it and check the serial output it doesn't appear to do anything. I tried it with 3.3v and 5v power and it still does nothing.

Any ideas why this particular model won't work?

@ joymonkey I presume you have searched the threads. http://wiibrew.org/wiki/Wiimote/Extension_Controllers also has some references to third party devices and the means to get them working.

Not sure why trying it with 5v would work when they are 3v3 devices. Pullup resistors are needed on each of the lines, and some of the threads within this forum have some I2C checking that you can use to help determine what isn't working for you with this device.

I suspect its the initialisation thats the problem.