I just forgot to say that i do not know java at all.
I know Oracle database and its 4GL development tools.
What i suggested to Omid was based on this experience.
What i know is that you have to keep both sides,
client and the database, to talk together with the
same character set to prevent code conversion. Oracle
describes that which character sets can be converted
to each other and which can't. If you have two
character sets that can not be converted to each other
then Oracle inserts a '?' for each character of data
which it receives.
Sorry for interruption in java discussions.