? (question mark) characters

Ok, I tried all the drivers currently available at http://jdbc.fastcrypt.com.
They all seem to correct the problem with long (>8k) SQL statements, but
they're all broken considering Portuguese characters like áéíóú (aeiou with
accent)... they are replaced by question marks (?)... any ideas? Should I try
to compile my own drivers? How?
BTW I am using JDK 1.3 from Sun (Solaris and Linux)...

--
Ricardo Pardini
rpardini@organox.com.br