ODBC, Delphi and BLOBs (images)

Hello,

I'm trying to access PostgreSQL database from Delphi via ODBC.
Everything works fast and reliably. The only problem are BLOBs,
images in this case.

I created the "lo" type according to the FAQ:

     create type lo (
     internallength=4,  externallength=10,
     input=int4in, output=int4out,
     default='',  passedbyvalue
     );

and then created a table and an index:

CREATE TABLE test_tab(nr int4, img lo);
CREATE UNIQUE INDEX test_inx ON test_tab (nr);

I attached a DBImage control to the "img" field and DBEdit to "nr"

When I insert "images" to the table manually, later  Delphi displays
it without any problem.

When I try to insert any image from Dephi, the value "0" is inserted
instead of any real OID value, which causes:

 "Unrecognized return value from copy_and_convert_field."

on a select attempt.

What can cause "0" to be inserted instead of any value, say 16648?
Have anyone ever had similar problem? How can it be solved?

It seems that the problem is caused by the Delphi-ODBC interaction.
With Access everything works well.

If the information I gave here is not precise enough or unclear,
please ask me for any extra details.

I'd appreciate any suggestions pointing me to the right direction.

Here are software versions and logs:

Delphi: 2.0
BDE: 4.51
Postgres - ODBC: 6.30.0248
Postgres: 6.3.2
ODBC Admin: 3.0.23.1

In case of UPDATE the psqlodbc.log looks like this:

conn=44173436, query='SELECT "img" FROM "test_tab" WHERE "nr"=255'
    [ fetched 1 rows ]
conn=44173436, query='BEGIN'
conn=44173436, query='UPDATE "test_tab" SET "img"=0 WHERE "nr"=255'
                                             ^^^^^^
                                             why 0?
conn=44173436, query='COMMIT'
conn=44173436, query='SELECT "img" FROM "test_tab" WHERE "nr"=255'
    [ fetched 1 rows ]
STATEMENT ERROR: func=SQLFetch, desc='', errnum=8, errmsg='Unrecognized
return
value from copy_and_convert_field.'


Andrzej