Procedure to Change the Character Set in oracle to support the local characters like unicode.

SQL> SHUTDOWN IMMEDIATE;
SQL> CONNECT SYS/password AS SYSDBA;
SQL> STARTUP MOUNT;
SQL> ALTER SYSTEM ENABLE RESTRICTED SESSION;
SQL> ALTER DATABASE OPEN;
SQL> ALTER DATABASE CHARACTER SET INTERNAL_USE AL32UTF8;
SQL> SHUTDOWN;
SQL> STARTUP;
SQL> QUIT;