Only certain IMs are counted in that 400; and only when you're using the default IM app. Google Talk IMs are included for free. And if you want to use somethi

Only certain IMs are counted in that 400; and only when you're using the default IM app. Google Talk IMs are included for free. And if you want to use something else, there are other IM apps out there that don't use T-Mobile's gateway.