u need to search now,i had forgoten,but i recommend u a page had discus it ,now i only know unite two files under X11 to one files,so u can get a locaable,i had use it to build chinput under slackware
,what a pity ,i had forgoten the detail
in fact the Slackware 9's GlibC has i18n support,but it lack some locales files,so once you add this locales files to the /usr/lib/i18n & /usr/share/locale, it will work perfect.