route each incoming mail 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!