IOS – Why are the iOS keyboard settings changing on their own

I have an iPod Touch — my first iOS device — and I'm trying to figure out how to set up the keyboard layouts, because I'm going to be typing almost exclusively Japanese.

I went into the preferences, added the Japanese 10-key, added the Chinese (traditional) handwriting recognition, and removed all the others. (I'm indifferent to the emoji keyboard layout, since it doesn't ever seem to appear, even when it's in the list.)

After a few minutes of using my iPod, the keyboard settings will have automatically changed. The Japanese romaji keyboard will have been added, and the Chinese handwriting will have been replaced with the English keyboard.

I find this confusing and frustrating. If I add these extra keyboards myself, then it doesn't muck up my preferences, but then I have a bunch of extra keyboards I'll never use, including the default keyboard.

I've been trying for a couple days to find a pattern (a particular app or operation that causes the keyboards to spontaneously change), but I've not found a smoking gun yet. One symptom is that when the keyboards change, when I go into the preferences, it's back at the top of the main screen, instead of wherever I was last (regardless of whether I was in the keyboard settings or not) — but I don't know the significance of that.

So a few questions about this:

• Is this new in iOS 4 or 4.1? Is it the sort of thing that Apple would recognize as a bug and fix in 4.2 (or even 4.1.x)?

• Is there a workaround? (I'm completely new to iOS so I haven't figured out all the workarounds for the OS bugs here yet!)

• Is there a way to set the default keyboard? (This wouldn't be nearly as bad if I could make the Japanese 10-key the default keyboard, but whenever 'English' is in the list, it makes itself the default, no matter where it is in the preferences list.)

Thanks!