Is Instant Messaging now running on GPRS (not SMS)?

[peteyspambucket]

I was just goofing around with my phone today, and I was in an area where I was only getting GSM coverage (not GPRS). I tried to launch "Instant Messaging", and it said something like "You are not in an area that is getting GPRS coverage". If Instant Messaging is now using GPRS, then we can chat indefinitely if with the Blackberry Unlimited plan (which I do). The version I am running is 4.1.7.

Can it be that we can now do Yahoo, MSN, AIM, and ICQ now without incurring a ga-zillion SMS messages on our bills? (If I'm wrong, pls let me know asap before I go wild on this thing!)

[andrebsd]

Wirelessly posted (BlackBerry7100/4.0.2 Profile/MIDP-2.0 Configuration/CLDC-1.1)

The built in program seems to use gprs to login, but sms after. As far as not getting sms charges, just use a 3Rd party I'm program such as IM+ and it will use gprs for everything.