i just bought a iphone 3gs a few weeks ago and when im in a 3g area my mail and other things automatically update and take money off my prepay account. ive lost about $30 now on nothing. i use wifi at home so don't use the 3g feature. ive called vodafone but they have been useless. they told me to put aeroplane mode on, but then i cant use my fone! please help.