T-Mobile, the fourth largest U.S. carrier, announced earlier this week that it would finally start offering the Apple iPhone 5 from April 12 with compatibility on its new 4G LTE network. What has grabbed the attention of many is the fact that the iPhone model that T-Mobile will be carrying is a slightly tweaked version of the A1428 model of the device, currently offered by AT&T.

Following this revelation, a concern has been raised that existing users of the AT&T variant of the iPhone 5, who want to try out T-Mobile’s new 4G LTE network on their device, will not be able to do so as their iPhone 5 model will lack the Advanced Wireless Services (AWS) radios that are found in the upcoming tweaked version of the T-Mobile iPhone 5.

However, thanks to a jailbreak mod, it’s now possible to get T-Mobile’s new 4G LTE speed on an AT&T variant of the iPhone 5 or an officially unlocked version of the smartphone from Apple itself. It should be noted that the jailbreak tweak in question will not work on a Verizon iPhone 5 as it does not have the correct LTE band.

It has been claimed that the iPhone 5 jailbreak mod can make AT&T’s A1428 iPhone 5 work on T-Mobile’s 4G LTE network on the 1700MHz band. The process includes loading a custom carrier file onto the iPhone 5 to enable T-Mobile’s LTE AWS bandwidths.

Below are the steps to perform the jailbreak tweak on your iPhone 5 model A1428 (via LEI Mobile):

1. Open Cydia 2. Tap “Manage” and then tap “Sources” 3. Tap “Edit” then tap “Add” and put the following URL into the text box: http://v.backspace.jp/repo 4. Once the URL is entered in tap “Add Source” and allow for it to download all of the repo’s info and packages. 5. After your iPhone has refreshed, tap the v.backspace.jp/repo field or go to the search bar and find the package CommCenter* patch… 6. Once you have found it, install it and then reboot your iPhone once completed.

7. After the iPhone has restarted, open Cydia once again. 8. Search for iFile. The free version includes basic features. You will want to purchase it to take advantage of all of the features. 9. Once you have found it, install it. No reboot is required, though you can do it just to be on the safe side.

10. Once iFile has been installed, close Cydia and click on this file from your iPhone and click “Open in iFile” 11. Once you’re in iFile tap “Unarchiver” and three files will show up above T-Mobile LTE.zip 12. At the top, tap “edit” and tap the dots with a check mark next to carrier.plist, carrier.pri, overrides_N41_N42.plist, and overrides_N41_N42.pri 13. Tap the clipboard icon at the bottom and tap “cut” 14. Now tap “done” at the top and tap the house icon at the bottom then tap Library, then tap Carrier Bundle.bundle (the one in blue), and then tap edit at the top again and tap the clipboard icon. Tap “paste” and it will auto inject the carrier files into the carrier folder overwriting the other files. (You may want to take a backup of these files just in case anything goes wrong.)

15. After the files have been placed, exit iFile and restart iPhone. After the iPhone restarts, allow it to acquire signal and display the T-Mobile logo then go to where you edit the APN settings (Settings –>General–>Cellular) click reset network settings. Once that is done, enable the LTE toggle and you’re good to go. The APN to connect to T-Mobile LTE is fast.t-mobile.com and the APN for Internet Tethering on T-Mobile is pcweb.tmobile.com.

For those who want to experience T-Mobile’s 4G LTE network, but are not really keen to buy the new T-Mobile iPhone 5, this jailbreak mod does have a go-for-it factor. However, there are some glitches.

As iDownloadBlog has pointed out, the trick won’t “make your AT&T iPhone work on T-Mobile’s speedy 3G DC-HSDPA 42Mbps network.” Given that, whenever you want to use DC-HSDPA on your iPhone 5 once you go outside T-Mobile’s LTE coverage (Baltimore, Houston, Kansas City, Las Vegas, Phoenix, San Jose and Washington DC), you will be out of luck. In addition, the hack also doesn’t support T-Mobile’s slower 21Mbps HSPA+ network.