Migration from odbc driver 7.x to 8.x

Hello list!
We have been using the PostgreSQL odbc driver 7.03.02.00 for a long time 
to access our PostgreSQL 8.0.3 database with Microsoft Access. Now we 
updated to odbc driver 8.00.01.02 and get the well-known problems with  
non-ascii characters. I have already found several threads in this 
mailing list and have come to the conclusion that it has been our fault 
to use an SQL_ASCII encoding in our database. So I set up a test 
database using UNICODE as encoding and tried to store some umlauts in it 
(using the new odbc driver). This worked fine; however, when I tried to 
access this new database using the old odbc driver, the umlauts were not 
displayed correctly.
Now my question is: How can I perform a smooth migration from the old 
odbc driver to the new one? Is there any special trick? If I change the 
database encoding, the old driver will fail to get the umlauts right. If 
I don't change, the new driver does not work. It will be nearly 
impossible to do an instant update of the driver on all computers.
Thanks a lot for your suggestions.

Christian

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