ODBC - Recordset missing value when i migrate to postgresql 8.1

I was migrated postgresql from 7.4 to 8.1.2.
It has some problem in our application,Microsoft Access, which query
data on postgresql through pgSQLODBC.

*Server *: Postgresql 8.1.2
OS : Linux Redhat 7.3
Encoding : UTF8

*Client *: Windows XP Service Pack 1,2
ODBC : PostgresODBC 8.01.0200 Unicode

*Application *: VBA on Microsoft Access
*Connection *: DAO --> ODBC

Set gWS_ODBC = DBEngine.CreateWorkspace("ODBCWorkspace", "orssss",
"", dbUseODBC)
'CURSOR SET (SERVER CURSOR)

gWS_ODBC.DefaultCursorDriver = dbUseServerCursor
'ODBC CONNECT CHARACTER

gODBC_str =
"ODBC;DSN=DSST;DATABASE=DSST;SERVER=192.168.1.12;PORT=5432;UID=aid;PWD=drmm;"
gODBC_str = gODBC_str & "C2=dd_;;CX=186503ab"
Set gCON_ODBC = gWS_ODBC.OpenConnection("Connection1",
dbDriverComplete, False, gODBC_str)

*Recordset *:
Set lTB1 = gCON_ODBC.OpenRecordset(lMYSQL1, dbOpenDynaset)
SQL :
Select m.Childno as Childno , 0 as act_data , '0' as org_data ,
'' as acc_whcd
from m_part as m

The result on recordset:

lTB1!Childno --> 'PK00302'
lTB1!act_data --> 0
but when I get data from
lTB1!org_data
it show error :
Not positioned on a valid row for GetData.
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Next : I'm change my sql to :
SQL :
Select m.Childno as Childno , 0 as act_data , 0 as org_data ,
'' as acc_whcd
from m_part as m

i can get data from lTB1!org_data --> 0
but it has error at lTB1!acc_whcd

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I have the same problem when select some user function on postgresql.

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I was not found this problem on
Database : postgresql 7.4
Encoding : UNICODE
ODBC : Postgresql ODBC 7.xx.xx...