Customize the bounce message

Would it be possible to add a feature to allow for custom text to be=20
added the bounce message?  I would like to make it clear when rejecting=20
for permerror that the sender should contact their own mail admins or=20
tech support and that the problem is on their end.

Now that I am rejecting on permerrors and hard fails like the sending=20
domain specified with "-all", senders are forwarding the bounce message=20
to my users via other mailboxes and asking us what is going on.

The bounce message has a very helpful link to openspf.net explaining=20
exactly what is wrong but since my mail servers are doing the rejecting,=20
the senders think this is our fault.  End users don't know what to do=20
with that bounce message link.

--=20
David Jones