I and a few others have suggested a shoutbox on the forums but this was denied.
Creating an application that would allow you to chat for such a small company (no offense) would be a waste of time because it wouldn't be used that much and i rather have the admins focus on something more important for the game.
If they could hire a programmer who could make this it would be another story and that might actually be a good idea but i doubt it would be worth the money because they won't make any profit with this (i am not going to pay for a chat function on my phone)