"Key switches keyboard layout while pressed" -- how?

[Derek Broughton]

Luka Renko wrote:

> Now you can use Compose key to generate accented letters - for example:
> <Compose> c c   => ?
> <Compose> c s   => ?
> <Compose> c z   => ?
> <Compose> s s   => ß
>  
> For a list of Compose combinations you can look
> into /usr/share/X11/locale/en_US.UTF-8/Compose file.

You know, I could have sworn I had tried this and it didn't work, but on
retrying, sure enough it does.  Thanks, Luka.
-- 
derek