Hi All. Library "Locale" from "Boost C++ Libraries" package has Jamfile.v2 in folder "build". Target "boost_locale" of library in that jam-file defined see below: lib boost_locale : encoding/codepage.cpp shared/date_time.cpp shared/format.cpp shared/formatting.cpp shared/generator.cpp shared/ids.cpp shared/localization_backend.cpp shared/message.cpp shared/mo_lambda.cpp util/codecvt_converter.cpp util/default_locale.cpp util/info.cpp util/locale_data.cpp : # Don't link explicitly, not required <define>BOOST_THREAD_NO_LIB=1 <link>shared:<define>BOOST_LOCALE_DYN_LINK=1 <threading>multi # Meanwhile remove this <conditional>@configure ; You can see: usage-requirements of target is not defined, and user of library must define symbol BOOST_LOCALE_DYN_LINK=1 in own project.... I wrote email to author of library (Artyom Beilis), but he reject my proposal of add usage-requirements to lib target. May anybody with right-access to boost repository fix this??? -- With best regards, Alexey Badyaev Russian Federation, Kemerovo