They are, and I could either do that, or swap the file in and out (rename via script as needed). I was hoping to come up with a way to gain the native ability to 'do the right thing automagically'.

That is not possible to do with .Xmodmap (unless you do the fileswitching), as the two keyboard layouts are exactly the opposite of each other at least for the +/= key (Nokia uses unshifted +, standard keyboard uses unshifted =).

It looks like LXDE does have the ability to do xkb. I just need to find out how Maemo 'knows' how to map each keyboard to the correct xkb file, then figure out how to map that into the chroot environment (since at least some of the paths aren't the same).