Following is a problem that I'm facing right now and perhaps could you give me a solution.
Consider a subcontrator hosting our company's mail solution, so our domain MX too.
Our users, when within our lan, are using perdition as a proxy server to retreive their mails against the outside subcontractor's server.
Now a Zimbra FOSS multi-server edition is installed within our lan and working well (congratulations to this good alternative/solution).
Next we have to manage the progressive migration as we don't want a big-bang migration for some reasons.
Our subcontractor don't want to do a postfix mailtertable forward rules based on users to redirect mails to our zimbra mta.
So i would know if our zimbra mta could play the actual perdition role by contacting the remote subcontractor server and retreive mails to give them internally using imap for example (we assume this way that passwords are same on the outside and zimbra servers).
Thanks in advance
P.S At least one beer will be offered to the winner ;o)