Storing multilingual characters in Oracle

Our database currently storing english characters now needs to store lanaguages like chinese, korean and Japanese. NLS_CHARACTERSET is currently WE8ISO8859P1. I need to store multilingual characters in approximately 20% of the tables. There are three options:

1. Alter the columns to NCHAR. =20
2. Alter database charachter set AL32UTF8
3. Create a new database with AL32UTF8 charcter set and do export import.

Are there any known issues of using Nchar on Oracle 9.2.0.4? I found on a metalink note recommending NOT to use nchar and rather change character set. Anyone has any bad experience with Nchar/Nvarchar2?

Is WE8ISO8859P1 a strict subset of AL32UTF8?=20

Or Option 3 is the best way to go. I am trying to avoid this option because of outage time I have to take for export and import.

Please share your experience.

Regards,

Sandeep Dubey

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