Root T-Mobile Galaxy S2 T989 running Android 4 Ice Cream Sandwich

Fortunately, T-Mobile released the Android 4 Ice Cream Sandwich update for their Samsung Galaxy S2 T989. But now it’s the time to root it while running the new ICS version and we do have a guide for it.
As you may know, rooting your device offers you more control over it, more customization options and the ability to install more apps. But flashing anything on your device can damage it if you are not careful and it can also void your warranty. So please note that we cannot be held responsible for any damage caused to your device. This method has been tested by us and proved to be safe, so you should not worry as long as you follow out instructions carefully.
How to backup T-Mobile Galaxy S2 T989
You should always backup your device before flashing anything and there are some options for doing it, fortunately. We have some guides and apps that will help you backup your apps, contacts, sms messages and call logs, and here they are: SMS backup & restore, Call Logs backup & restore, Appbak, how to sync Contacts with Gmail.
To make sure that your files are safe, we suggest you to copy them on your SD card.
Once you performed the required backups you can proceed to the rooting procedure, which is pretty simple, actually.
How to root T-Mobile Samsung Galaxy S2 T989
First you have to make sure that you meet the following requirements:

• Have the latest version of Kies.
• Have USB Debugging enabled on your device. It can be enabled at Settings > Developer Tools.
• Your phone is charged to at least 40%.
• Kies, any antivirus or firewall software is disabled.

Now you will have to download the root file, CWM and Odin and copy the root file to your device.
After that connect your USB cable to the computer, but not to the device. Then turn off your device and turn it on while pressing the volume up and down buttons. While you keep the buttons pressed, connect the USB cable to the device.
Your device should enter download mode now and you can launch Odin. You will see an “Added” message in Odin and this means that your device is connected to the computer.
Click on PDA in Odin and select recovery.tar.md5, the file you just downloaded. Without changing anything else in Odin, press the start button and wait until it finishes.
Now you will have to turn off your device again and then enter recovery mode by pressing volume down + volume up + power buttons simultaneously.
Here head to Install zip from sd card > choose zip from sd card, select root.zip and then Yes. Once it finishes rooting the device you will have to reboot it.
And you are now using a rooted T-Mobile Samsung Galaxy S2 T989.