This isn't obvious, because the default input is "scim" and the one you need is "scim". (yes, they're the same--I explain below)
- Install alternate language support [for example Japanese]
- Can do at install, but there is also Applications > Add/Remove Software. Look towards the bottom for "Languages"
- Expand your language, there may be extra features. For example, Japanese has an input pad, and *maybe* handwriting recognition if I can find it... (next how-to?)
- Packages such as scim.x86 should be installed then. To double check, open a terminal and $ yum info scim <== check for "Repo: installed"
- System > Preferences > Personal > Input Method
- The default setting is "Follow the system-wide configuration[SCIM]". Wrong scim. No panel switcher applet.
- Bottom choice: Use custom input method "scim". <== that's the right scim
- Log out / log in to restart gnome
- Upper right corner: right click > SCIM Setup
- Customize how everything works here.
- For a Japanese keyboard (if set up in Gnome correctly), the traditional language input switch keys can be enabled by FrontEnd > Global Setup > Next input method [...] > Key code [...] > (press the key you want) > Add
- A warning message may appear about settings not taking place, but for me all settings were enabled correctly.
Voila! It may take you some experimenting with SCIM setup to suit your liking, but once it is setup you need not mess with it again. enjoy