This stupid thing happened to me as well. I earned free call credits from my teleco around 15$. And even though i had switched all apps to always ask or only wifi something i happen to pick up my phone and found ovi maps on and downloading map which consumed 12$ of credit withing few secs. I swear it must be hacked by my teleco to take away my free credits as i had not switched on the maps or any setting in maps to use gprs.