How to Update Samsung Galaxy S2(I9100) to Jelly Bean 4.1.2 and Install Khmer Unicode

The latest official Rom for Samsung Galaxy S2 is 4.1.2 which is the most stable and reliable OS with lot of improvements. It is recently received latest Jelly Bean Over-The-Air (OTA) update from Samsung via Android 4.1.2 VJMS4 official firmware.

Step1- Download the require files: 

Download Jelly Bean 4.1.2 for Galaxy S2 (I9100)
Download Odin
Follow this guide for how to update the firmware 
Download PhilZ Touch 5 Recovery

Step2- Rooting
Put your phone into Download Mode, then open up Odin. In PDA section click and browse to the downloaded Philz Touch Recovery.tar file. Click apply and wait for phone restarts.

Step3- Install Khmer Unicode
Download  Khmer Font
Copy the downloaded Kh-Flash_ICS-JB_Ver.1.zip into USB Storage or SD Card. Then boot into Recovery Mode and choose apply zip from USB storage or SD Card.

To type khmer, you need to install Multiling Keyboard and Khmer Plugin from Playstore.