Adding long text to a text field generates an error

I'm using PostgreSQL 7.4 on a Windows 2000 server with cygwin. All is
set up just fine. The database works just fine, and ASP is connecting
to the database through a DSN just fine. The only problem I seem to
have is adding a large amount of text to a text column in the database.
I can enter up to 8,118 characters (including spaces), but when I go
over that amount, I receive the following error:

Microsoft OLE DB Provider for ODBC Drivers error '80040e21'
Multiple-step OLE DB operation generated errors. Check each OLE DB
status value, if available. No work was done.

This error doesn't mean much to me. I've spent a month researching it
and trying to figure out what it means in our situation, but I have yet
to resolve it. Thus, I'm turning to this list to see if anyone has any
ideas or has tackled this problem before.

I've tried using the appendChunk method in ASP to add chunks to the
field in the database (this worked before for us on a Linux box running
ChiliSoft ASP), but I get another error saying that the method is not
supported. We are using psqlODBC to connect with the DSN--I do not know
if this driver has anything to do with this circumstance.
I am currently using ADO to update the database, but I have used a
standard SQL INSERT statement for testing, and I get the same error and
problem. When I've run an INSERT query against the database itself
(from the command prompt), it won't update the record when I try
inserting more than 8,118 characters into a text column.

I've double-checked to make sure the column is of datatype "text" and
not anything else. It is. So, it should accept unlimited text, right?

Has anyone seen this problem before? I need help ASAP because our
client is refusing to pay until this is resolved.

Thanks,
Ben