The International Components for Unicode(ICU) is a C and C++ library
that provides robust and full-featured Unicode support on a wide
variety of platforms. The library provides:

Calendar support
Character set conversions
Collation (language-sensitive)
Date & time formatting
Locales (140+ supported)
Message catalogs (resources) 
Message formatting 
Normalization 
Number & currency formatting
Time zones
Transliteration
Word, line & sentence breaks