--On Monday, January 29, 2007 9:03 PM +0100 Magnus Holmgren
<[EMAIL PROTECTED]> wrote:
So, it is well established that mail from a domain doesn't have to be
sent from the MX for the domain. But the converse should be true,
shouldn't it? I.e. an MX for a domain is normally a legitimate deliverer
of mail from that domain (if it delivers any outbound mail at all).
It will likely be a source of bounce messages but it need not send those
messages directly. It could still send them through another server
designated for outbound delivery.
It's probably a fair assumption that it won't be the source of unauthorized
mail for the domain, unless it's been usurped.
