data is not working! i have 3G, can make calls, send and receive texts, etc but it wont connect online. i've been on gophone for years...so long my sim card still says cingular lol. any i am grandfathered into the $20 unlimited internet plan att offered way back when. its worked on blackberry's, the samsung galaxy, etc and have never had a problem browsing, downloaading, etc. but this is my first iphone. any suggestions???