Just thougt I'd reply a soulution if anyone is looking for the same thing.
If you have an Oracle 9i or better one soulution counld be to use the following syntax:
Ex1. Converts the string "Test" from default character set to UTF-16
SELECT CONVERT('Test', 'AL16UTF16')
FROM DUAL
Ex2. Converts the string "Test" from character set UTF-8 to UTF-16
SELECT CONVERT('Test', 'AL16UTF16', 'UTF8')
FROM DUAL
This however didn't work for me as my database doesn't support the AL16UTF16 character set.
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