roting one incoming message to two downstream smtp servers

Hello,

I'm looking to test out two different Anti-SPAM solutions and would
like each incoming message to be routed to two SMTP servers, like so:

Internets --> [ mx1 ] --> [ mx2+anti-spam1 ] --> [ mailstore1 ]
|
|
--> [ mx3+anti-spam2 ] --> [ mailstore2 ]


Where for each incoming message, mx1 would send a copy to mx2 and mx3.
Is there way to do this with postfix?

thanks a bunch!