Need help with redefining locales

I'm having trouble with like et.al. as there is no single character
in et_EE locale (on linux at least) that is bigger than all the others.

I would like to modify my locale definition files so that char(255)
would always sort after all others but I can't find docs on modifying
the locales

So i have a couple of questions:

1) what file must i change and how to get char(255) out of the Y-group
and into a separate group that sorts after all others
(I guess the file is /usr/share/i18n/locales/et_EE, but I'm not so
sure about the how part)

2) how can I then turn this file into the various LC_* files

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Hannu