Update Field Using Value From Linked 2000 Sql Data

I'm trying to update a field (tmpRequestID) in a SQL Express table (tblTSubRequest) using a value in a SQL 2000 database field (fldtmpRequestID) in the dbo.NewPurchase table.

The procedure I thought would work is:
USE [tempPurchase]
GO
/****** Object: StoredProcedure [dbo].[UpdateSubfldRequestID] Script Date: 07/11/2007 15:01:51 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
ALTER PROCEDURE [dbo].[UpdateSubfldRequestID]
AS
BEGIN
-- Insert statements for procedure here
UPDATE tblTSubRequest
SET tmpRequestID = tblRequest.fldRequestID
FROM tblTSubRequest INNER JOIN
[NGTXA4-RSMSZ-01].NewPurchase.dbo.tblRequest ON tblTSubRequest.fldRequestID = tblRequest.fldRequestID
WHERE (tblRequest.fldUpdateCode = 99)
END

It appears that the procedure cannot read the field value on the 2000 server and the 2000 server is linked to the 2005 express edition.