[Bricks]

Hi guys! Maybe it was asked before, I searched but found nothing helpful. My Blackberry Curve 8520 sends/receives data every 30 minutes, and the amount of data is always around 50 kb. Even at night every 30 minutes. The only way to stop this is to switch data transfers off.
I thought that it is some kind of software that updates its own information [ weather, facebook etc.] - uninstalled all programs that could do that, but nothing helps, so what could it be? Thanks!