All email forward a copy to testing server

[postfix users]

Hi,

I am migrating the Exchange 2000 to Exchange 2010, but before we switch over
to new server, I want make a copy of email to new server for testing.


Existing Config:

Postfix -> Amavisd -> Exchange 2000

Here what I want :

Postfix ---> Amavisd -> Exchange 2000
           ---> Exchange 2010

Is it possible?

Or it is better forward all email before Postfix?

email -- some program? --> Postfix ---> Amavisd -> Exchange 2000
                                   --> Exchange 2010

Many thanks in advance.

Regards,
Paul Margaillan