I'm currently trying to configure a Zimbra Soho solution which will need to work without any MX records. I have installed Zimbra, disabled DNS lookups and set the proper relay smtp server. Outbound mail works fine but internal does not. Postfix complains about the source and destination being the same? (I will fetch the exact error from zimbra.log and post later). Fetchmail has been configured but I was wondering about how to set this up properly. In Exchange, you have the ability to add an extra email address and set this as the primary so this will be used when a user sends mail. How is this done in Zimbra? By creating an extra email domain? Basically I want a setup in which Zimbra will fetch the mail from the mailserver of the provider and sending it itself while using the correct mail domain.

Thanks in advance,