Lord Nightmare, you can create own mapping based on <geoip> (ip -> Country -> language prefix).
Of course, it will be very inaccurate. Still, better than nothing. There is also
GeoIpCity.
Also, you can create and auto-populate local database with information about (ip -> language prefix)
when that info come to knowlegde to sm in later connection stage, so next time that info will be available for you.
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