Gamepad - buttons work but d-pad doesn't

[Prizm]

hi guys,

I've got everything up and running with Dolphin, and I've been trying to configure my Sidewinder gamepad. It's detected in the Wiimote settings and I can see the dot move around in the analog area where you test up/down/left/right.

I've configured the individual buttons, but when I load up Mario Bros Wii, my d-pad doesn't work. The buttons however, work in the game exactly as I programmed them.

How do I enable the d-pad? I have already ticked the option for "sideways wiimote" and I don't know what else to do.

thanks