There are three areas that should be looked at if you're having trouble entering or displaying UTF-8 characters in Sakai:
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A good reference for Oracle 9i (especially Figure 2-8 & 2-9) is at http://download.oracle.com/docs/cd/B10500_01/server.920/a96529/ch2.htm
If that doesn't work or it gives the error "ORA-12712: new character set must be a superset of old character set" you can try
ALTER DATABASE CHARACTER SET INTERNAL_USE AL32UTF8;
The above command will skip the check of character set subset or superset.
3) Make sure the (MySql) connector is defined for UTF-8 encoding in the sakai.properties file. Note that previous releases of Sakai had an incorrect default value:
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