Writing BLOBS to pgsql via ODBC using VB

I am having problems while trying to insert a BLOB into a pgsql table using VB.
The error i get is:
S1090: [Microsoft][ODBC Driver Manager] Invalid String or buffer
length

I am using postgresql 7.1.3, Postgresql ODBC driver 7.01.00.07 and RDO 2.0

Have you any idea why i get this error?

Additional infos:

Here is the table definition:
CREATE TABLE MYTABLE (
MAIN INTEGER NOT NULL PRIMARY KEY,
OBJECT LO
);

Here is the code:

Private Sub Command1_Click()

Dim rdoConn As New rdoConnection, rdoRS As rdoResultset, SQL As String
Dim numfile As Integer
Dim filesize As Long
Dim query As rdoQuery
Dim chunk() As Byte

' DB Connection
With rdoConn
.Connect = "uid=myuser;pwd=mypwd;DSN=BLOB_TEST;"
.CursorDriver = rdUseOdbc
.LoginTimeout = 3
.EstablishConnection rdDriverNoPrompt
End With
Set query = rdoConn.CreateQuery("MyQuery", "select * from mytable")
Set rdoRS = query.OpenResultset(rdOpenKeyset, rdConcurRowVer)
If rdoRS Is Nothing Or rdoRS.Updatable = False Then
MsgBox "Cannot create rdoResultSet"
End
End If

' Now insert the record in the table
If rdoRS.EOF Then
' Insert a new record
rdoRS.AddNew

' The MAIN field
rdoRS!MAIN = 2678

' Get a file number
numfile = FreeFile

' Open the file i've to insert in the table
Open "c:\myfile.doc" For Binary Access Read As #numfile
filesize = LOF(numfile)
If filesize = 0 Then
MsgBox "Unable to open the file"
Close
End
End If

ReDim chunk(filesize)

' Read the file into the array
Get #numfile, , chunk()

' Try to insert
rdoRS!OBJECT.AppendChunk chunk()

' In the update statement i get the error
rdoRS.Update
Close #numfile
End If
End Sub

Regards,

Doct. Eng. Denis
Gasparin denis(at)edistar(dot)com
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Administrator http://www.edistar.com
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