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Providing Globalization Support
The basic Java Archive (JAR) files, ojdbc5.jar and ojdbc6.jar, contain all the necessary classes to provide complete globalization support for:
Oracle character sets for CHAR, VARCHAR, LONGVARCHAR, or CLOB data that is not being retrieved or inserted as a data member of an Oracle object or collection type.
CHAR or VARCHAR data members of object and collection for the character sets US7ASCII, WE8DEC, WE8ISO8859P1, WE8MSWIN1252, and UTF8.
To use any other character sets in CHAR or VARCHAR data members of objects or collections, you must include orai18n.jar in the CLASSPATH environment variable of your application.