First you need to identify what locale are you database (use the dbaccess for this):
Code:
echo "select * from sysdbslocale " | dbaccess sysmaster
Variable DB_LOCALE must be set on the server, at the client side you need to use the variable CLIENT_LOCALE
obs.: the DB_LOCALE/CLIENT_LOCALE must be set in the ODBC configuration, the ODBC ignores the values defined in the setnet32 and enviroment variables:
Database Locale