GAMECOM Plantronic Headset for XBOX

[Bionic]

I have just bought a GAMECOM Plantronic Headset 367 5.1 surround(http://www.headsetsolutions.co.za/computerand-entertainment/gamecom-367.html) and want to use on my XBOX.I know it has a 3.5mm jack so i will need to get a converter for 2.5mm.

How would i get gameplay and chat through the headset instead of just chat like the XBOX headset?