Blackberry with Movistar Prepago only for Messenger (BBM)

[cafeconleche]

I have an unlocked Blackberry Curve and a Movistar prepago SIM. I want to be able to get a data plan only so that I can use Blackberry Messenger (BBM). Any idea how I can do that? I've been trying to speak to customer service but don't quite understand all the IVR options. I checked on their website but couldn't find any way to automatically activate data for BB.

Thanks so much to anyone who can help. I'm a BB newbie.