I've been trying to redirect email to an external host. I've been using the
virtual_alias_domains method. This occasionally works but where there is a SPF on a sender domain, it fails tragically. The destination server just spits out the email because the email isn't coming from a designated server. Quite fair IMO.
I want to forward the email messages so that to the destination server, it looks like a brand new email that's being forwarded, originating from my own server, so it's much more likely to make it into the inbox rather than the spam filter (or just being dropped).
Is there any decent way to do this? I imagine it actually just requires re-headering the email but I've no idea how to transform them.