> After successfully executing a statement with the Firebirdsql driver,
> we always get an exception:
> ...
> GDSException: org.firebirdsql.gds.GDSException: message length error
> (encountered 64, expected )
> ...
>
> What does this mean, and where can I get a list of possible error
> codes?

recently I got the same problem. I was executing stored procedure that
returns result set using EXECUTE PROCEDURE ... instead of SELECT *
FROM ... via java.sql.Statement. Using SELECT instead of EXECUTE
PROCEDURE solved the problem. I have posted this question to
firebird-devel list and will keep you informed if I get any response.

Best regards,
Roman Rokytskyy

P.S. I have updated execption handling, now message will be "message
length error (encountered 0, expected 64)", which is correct in this case.