[rt-users] Fwd: Returned mail: unknown mailer error 255

[bill at daze.net]

> was done was to create a ticket via email and respond via RT Web UI......in 
> which the response mail was never received by the requestor (in this case, 
> i was both the requestor and the Web UI user/responder......)

If you are both the requestor and RT user, RT will not send e-mail.  This
is a FAQ.  I'm not sure what your other problem is though, nor do I know
what RT's "magic headers" are.