GamePad Hotkeys in 2.0.6

[SeanEBaby]

I'm getting errors when I try to set gamepad hotkeys in 2.0.6, the same error can be seen in the phaser example here

 

Trying to set a hot key like this

game.input.gamepad.start();button0 = game.input.gamepad.pad1.addButton(Phaser.Gamepad.BUTTON_0);       button0.onDown.add(function() {         selectGem();       })

just sets button0 to null...  I tried looking at the changes to gamepad in the source but my knowledge isn't good enough to figure out what's wrong.  Any help would be appreciated.