Players may use Teamspeak 3 during maps/games on my Cod4 open warfare server. But it runs outside and independent of the game itself. There is a COD4 channel/room within the client's window when they log in to my Teamspeak. But I have never known Teamspeak to work well from within COD4. I remember the havoc Overwolf caused. And there is always the Z key talk in game in some mods by some servers, which beats T key text chat.