1) Set multiple languages in OS X by going to System Preferences->Language & Text->Input Sources-> and add multiple languages.
2) Restart the computer
3) Go to the flash/AIR app and focus a text input.
4) Switch to other application like a browser.
5) Switch back to the flash/AIR app and change the language by keyboard shortcut or by clicking on the top OS X menu bar by clicking on the flag of the language.
Language cant be changed to other languages.