I think this is already done for KDE when kpersonalizer it prompts the user with the Country/Language setting. When I had LANG="en_US.UTF-8" set it automatically selected US and English for me only requiring me to click on OK. Also for the KDE case you have to remember to install the right kde-i18n package for the particular language you wish to use.
If you notice anything that KDE does not do properly please let me know. If you have any questions regarding the kde-i18n packages themselves the maintainer is Nočl Köthe <[EMAIL PROTECTED]>. Thanks, Chris
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