Thanks all:

seems to me that there are two ways to do it, or, rather, that for those
of us with US/UK keyboards, we may need to use two methods
simulataneously, at least on *nixes.

The global solution (on *nixes) is to use Jamie Zawinski's xkeycaps
which is a graphical front end (and more) for xmodmap. It's actually
much easier to use than the man page suggests: you simply find a
keyboard which matches your own and can then allocate different values
to keys you don't use graphically: for example, my [Home] now gives è
while Shift + [Home] gives È. And since Xwindow is the big boss
responsible for the keyboard, graphics and all that, it'll work on
any/every program, Squeak included. 

This might be all you need: for example, I have a lot of keys I never
use (the whole numeric pad, and a few more) and just need Italian and
Spanish accented vowels, plus the odd French and Spanish accented
constanant and maybe a few German/Hungarian/Brazilian vowels too. That
gives me 20+ keys to play about with. The trick is to avoid re-mapping
keys you, or the O.S. might want to use in their original form!

But if you didn't have enough spare keys, chances are that you'll need
to use xkeycaps to allocate a few accents to keys and then use Torge's
changeset to combine them with vowels. 

Thanks again, everyone: now there are no excuses for spelling mañana to
rhyme with banana!

Cheers

John
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