Zimbra and outbound DKIM signed mail
I've just started looking in to DKIM and DomainKeys. We've been publishing SPF records on our domain for a few years so thought I'd now start looking at DKIM.
My understanding of the current status of DKIM is that Zimbra itself can't add the headers to outgoing mail yet, and that it also can't verify incoming DKIM signed messages until amavisd supports it. Is that right?
I found a bug in bugzilla (https://bugzilla.zimbra.com/show_bug.cgi?id=11524) which currently has ASSIGNED status but who knows when that will be implemented, probably with v8 in a couple of years I guess.
Currently we route all outgoing mail through a relayhost which is a private
postfix VPS. Zimbra uploads the mail to our private relay through an SSH tunnel, then the private relay sends it out onto the internet.
So there's nothing to actually stop me from adding the DKIM signature at our postfix mail relay? Then receiving servers that support DKIM can at least verify our message signatures.
Is that right?
Or would Zimbra need DKIM support itself before we could do this?