multiple domains/alias to non zimbra server

[itlime]

Here is what I would like to do. I have a domain called foo.com and that is setup as the main domain on my zimbra server. I also have a domain entitled exchange.foo.com. the exchange.foo.com domain is managed by exchange. Some of my users are hosted by zimbra and some by the exchange server. In my current mail solution I create alias for the exchange users on the postfix box and use a transport relay to send the exchange domain to the correct server. However when I am unable to do this in zimbra. I do not want zimbra to forward all foo.com mail to exchange.foo.com mail server, but only certain users. How do i do that? Below is a little chart that might illustrate this a bit better

Mail from Internet-> Address to Mikey@foo.com->Mikey, has a zimbra mailbox-> zimbra accepts and sends to his box.

mail from internet->address to Keith@foo.com ->Keith has an exchange box, as determined from an alias, ->zimbra forwards to exchange.foo.com Mail server.

[captainmish]

Ive just done exactly this in Zimbra, its almost the same as "normal" postfix, just with some zimbra wrappings..

First get the current transport maps with zmlocalconfig | grep transport, then update it to include your new transport file with
zmlocalconfig -e postfix_transport_maps={/new/transport/map},{pre-existing zimbra map, taken from step above}

So my transport_maps directive for example is now:
pcre:/etc/zimbra/aliases-transport,proxy:ldap:${zimbra_home}/conf/ldap-transport.cf

Once its changed, `zmmtactl reload` will rewrite the config files and reload postfix for you.

Hope that helps

[itlime]

So i would need each alias in my new transport map? Is there a way to do it via any zimbra GUI. As this is a common task (20 times a month at least), making every change in this file would not be ideal. not to mention due to other domains, i need about 700 alias and managing that text file is not ideal. We currently use postfixadmin on our current setup to streamline administration. Any other suggestions as to how I can achieve similar administrative results?