Multiple layouts for one language

I'm not sure if this will need to get explicitly implemented, but different languages have multiple keyboard variants. With a touch keyboard, there will conceivably be a proliferation of new layouts, and they will be different than the physical ones, i.e. they won't be in any system database, so they won't be selectable from the system controls. It may even happen that the keyboard will be the only source of alternative layout knowledge.

There need to be accommodations for this. Perhaps related to providing a terminal keyboard layout.