Fortimail gateway mode

[Nemat]

We have zimbra mail server in our environment, the server reside in a zone in another zone we have a proxy server woth MTA above of this we have a fortigate appliance. We brought new fortimail but we don't know now where we have to put it between the proxy and mail server or between the fortigate and proxy? or we just we have to replace it with our proxy? Thanks.

[Nemat]

I forget to mention that, the proxy works as gateway for the mail server. So if we placed fortimail between our Fortigate and the proxy, can we setup the Fortimail as MTA? I mean just to scan the traffic and then to forward it to the proxy server to distribute it to the right mail server?