i'm going to mexico for a couple of weeks. wondering if possible to change the apn settings to allow for the use of a prepaid card from IUSAcell or other cdma carrier, at least for local voice calls? i have the huawei ascend from metropcs running CM7. can't access apn settings on CM7 but would be willing to flash a froyo rom for temporary use while traveling in mexico. right now, best option seems to buy a $30 unlocked phone and buy a prepaid card down there and just use my ascend at wi-fi spots to keep up with my facebook stuff.