XDA member gromky presents the basic steps to get simplified Chinese working on Rhodium. This was tested on Energy ROMs but should work on any other. According to the developer, many other options are available around but they seem to be more complicated or having serious issues.
Three steps must be done to have it working: install fonts, install input method, and Change system default font. To avoid unwanted behavior, be sure to read all the installation instructions and all apps must be installed on main memory to ensure proper display.
Originally posted by gromky
Simplified Chinese Input (official HTC version)
I had a terrible time getting simplified Chinese to work on my Touch 2 Pro. I tried everything. Finally I had a solution. I will share it with everyone because it was so much trouble for me.
Everyone will tell you to go to http://forum.xda-developers.com/showthread.php?t=700311 and follow the instructions there. No, this is only for traditional Chinese input! The fonts are OK but the input is not suitable.
Next, everyone will tell you to download Sogou, QQ, A4, or other Chinese input method. This is not suitable! Why? Because these applications interfere with the keyboard of Touch Pro 2. With some, the shift key did not work and I couldn’t write capital letters. With others, the FN keys did not work (symbols like ;:’& were remapped to other keys!) One of them remapped the entire keyboard, making text unusable! I needed the official HTC input. After hours of searching, I finally found a version that works. Download from this thread http://forum.xda-developers.com/showthread.php?t=693907. It says it is for a specific model of phone, but it works fine on mine. The only problem is that the soft keyboard is squashed while the keyboard is pulled out, but if the keyboard is out, no need to use the soft keyboard.
My steps to get simplified Chinese working on Energy rom. This should work under any other rom as well