-- Posted by sdkarr at 11:09 pm on Aug. 30, 2008 so i know with verizon you can update your roaming capabilites by calling a number. so you hook up to the nearest tower. does t mobile have this function?? -- Posted by Crazy snake at 3:10 pm on Aug. 31, 2008 Most mobile phone companies have this function. Simply ring up your providers customer services, and ask for the roaming section, and ask queries there -CS -- Posted by YeahBoii at 2:34 pm on Sep. 2, 2008 I have Alltel and you just do *228... -- Posted by hI jAMES at 4:19 am on Sep. 3, 2008 Most services have it.  Call them or look up the code online.  Customer Service is probably the best option. -- Posted by Cingular Wireless at 12:00 pm on Sep. 3, 2008 no. tmobile is gsm Not cdma -- Posted by Enzeru at 10:29 am on Sep. 4, 2008 Cingular is right. As far as I know with AT&T and T-Mobile, all you have to do is travel and it connects to nearest tower automatically within in milliseconds it registers you. You do not have to call in or anything.