Basically I would like to setup the Zimbra server as a collaboration suite, but not use it as a mail server for sending outbound mail. I want to use our existing external accounts for exchanging e-mails, but have the added functionality of everything else that comes with Zimbra. I understand that the Zimbra accounts need to be there, I just want an option so that when you create a new e-mail message you can set whatever account you want as the default.
It's very similar to what is being done for using the same account for forwarding/replying to messages as the message was sent to. | 
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