Here goes another of my bulleted lists:
• Jailbreak.
• Install BSD subsystem.
• Install Term vt100, MobileFinder, Erica’s Utilities, MobileTextEdit.
• Restart the iPhone.
• Go into Settings > General > International, and turn on any language and then turn it off. This will create a hidden system file called .GlobalPreferences.plist.
• Open MobileFinder, and hit “Settings”.
• Enable “view system files” or something like that. Exit Settings. Exit MobileFinder.
• Open Terminal.
• Navigate from your home directory to /private/var/mobile/Library/Preferences.
• Once you are in that directory, type in this command:
plutil -c xml1 .GlobalPreferences.plist
• This converts the plist file to XML, making it simpler to edit in MobileTextEdit.
• Open MobileFinder, and navigate to /mobile/Library/Preferences.
• Double-tap .GlobalPreferences.plist so it opens in MobileTextEdit.
• Look for a line that says:
<string>en_US</string>
• Make a new line under it that says:
<string>zh</string>
• Hit save and exit.
• Restart the iPhone and then open a program like Notepad, and you will see a small globe next to the spacebar (if you did everything correctly).
DO NOT GO TO SETTINGS > GENERAL > KEYBOARD/INTERNATIONAL. It will erase your hard work.
This is how I enabled Japanese input on my iPhone. I typed all these instructions on the phone so thanks for your patience and good luck.
さよなら。。。がいじん。