Originally Posted by orateam
I've done this a few times with T-mobile roms.
List the detail step by step methods you took, i'll see if you missed something. I was going to create a porting how-to thread but i'm too lazy.
Perhaps yours will serve as one.
Okay, here is a quick breakdown:
(The rom is question is based on the official Verizon 4.3 TW build)
1) I copied apns-conf.xml, GlobalConfig.jar, SecPhone.apk and more or less any library file with 'ril' in the title from the old rom to the new.
2) I edited build.prop to replace every reference to Verizon to reference T-Mobile, including device names
3) I did a factory reset (inc cache and Dalvik), installed the repackaged rom, then installed a T-Mobile 4.3 TW friendly kernel.
4) The default apn was epc.tmobile.com, which I had to change to fast.t-mobile.com to get LTE. After this change EVERYTHING net related with the exception of receiving phone calls worked.