problem updating from form

Hi,

I have a problem that has me stumped. We have a table that is the main
table in a production Microsoft Access application. Our users are
complaining that sometimes they enter data in the form, move off of the
record & then upon returning to the record the data reverts back to what
existed in the field prior to the entry. These complaints have recently
become more frequent. This is an intermittent problem, but I have been
able to replicate the issue consistently on one particular record. We
are using PostgreSQL 8.1.4 on Red Hat, Microsoft Access 2002 &
psqlodbc_09_00_0200. I can update the field successfully in the table
in Access, but not in a form. I have isolated the table, removing any
foreign keys from the table. There aren't any triggers. I created a
new Access DB with only the table & a crude form with only two fields,
the primary key & one other. In ODBC I made sure that row versioning
was set as true and Text as LongVarChar was set as false. We have
vacuumed, reindexed & performed a full vacuum on the Postgres DB
multiple times. None of these actions have had a positive effect. I
created an identical copy of the table & imported all of the data, over
194,000 records, into it. I saw the same problem results until I
removed all, but about 20 records. Only then was I able to get the
update from a form to stick on our test record.

Here is the table structure with the foreign keys removed.
CREATE TABLE "Production_Tracking"."tbl_Assemblies"
(
"BarCode" varchar(12) NOT NULL,
"PartNumber" varchar(32) NOT NULL,
"LRU" varchar(20),
"PartsListRev" varchar(10),
"SerialNumber" float8,
"MTN" varchar(15),
"DocNum" varchar(50),
"Comments" text,
"SupplierNo" varchar(7),
"DrawingNoRev" varchar(10),
"WorkOrder" varchar(8),
"BldStdRev" varchar(15),
"Quantity" int4 NOT NULL DEFAULT 1,
"Salesorder" varchar(8),
"WOQuantity" int4,
CONSTRAINT "pkey_BarCode" PRIMARY KEY ("BarCode")
)
WITHOUT OIDS;

I can provide the ODBC logs if helpful.

Thank you,
Karen