Problem with Character Set

[William]

Hi all, please help, let me explain my working environment first,
Client side:
Chinese windows 98, Delphi4/400(Configure Page code as CN-1, 037/1114)
Server side:
AS400 Single byte OS., support Portuguese character set.

When I run a query to search someone from a AS400 file thru Delphi4/400 on
Client side, such as:
SELECT * FROM dimp246 WHERE indname1 = 'ABEL BRAND? DA FONTE'
the person cannot be found, I noticed that it is because of 'ABEL BRAND? DA
FONTE'
contains a Portuguese character '?',
if I run the same query directly on a terminal of AS400, the record is
found.

Could anyone tell me that what's wrong? Character set conversion?

Thank you.
William Ko