Recordset not updatable

Hi,

after trying around for two evenings and browsing the usenet in vain,
I hope that someone reading this can help me with the following
problem:

I use postgresql 7.3.4 on a linux box and the postgresql ODBC driver
version 7.3.200 on a windows 2k box.

My program is written in Delphi 6 PE with a self-made derivative of
KADAOPE for database access using DAO. Reading and writing Access
databases using DAO recordsets with Jet workspace works fine. Reading
Postgres Databases using ODBC workspace works fine too. The postgresql
ODBC driver options are the default values.

Problem: I cannot get an updatable recordset.

CursorDriver is dbUseDefaultCursor.
recordset is opened with dbOpenDynaset
Example: DAORecordSet:=
FDAODatabase.CoreDatabase.OpenRecordset("SELECT * FROM mytable where
id1=4711", dbOpenDynaset).
mytable has a compound primary key (id1,id2).

DAORecordSet.Updatable is FALSE, and, consequently, DAORecordSet.Edit
fails with a write protection error.

I then tried and changed the parameters from dbOopenDynaset to
dbOpenDynamic, 0, dbOptimisticValue. But this makes
DAORecordSet.MoveLast fail with "Illegal operation" while the
recordset still is not updatable.

After updating the driver to version 7.3.208 from
http://www.geocities.jp/inocchichichi/psqlodbc/, MoveLast fails with
an Access violation error at ... in psqlodbc.dll.

Is there anybody out there who got psqlodbc to open updatable
recordsets via DAO? Any hints?

Many thanks in advance!
Boris