I have a Gevey Ultra s for my GSM Iphone 4s. I am currently running IOS 5.1 and modern firmware version 2.0.10. T-mobiles 1900 mhz band is active in my location, however the iphone is only utilizing edge, while my htc g2 is showing full bars of 4g. Is this because of the Gevey ? and if so, is there anything i can do about this ?