>
> Connecting an analyzer on the network cable reveals
> that it seems to send the same authentication strings
> as my Exim and the server responds with the same "535
> 5.7.8"-failed message, then the client starts sending
> a "MAIL FROM: <xxxx@???>" message which becomes
> OK'd by the server! The dialogue continues and
> eventually the mail becomes delivered properly.
>
This suggests the server also permits relaying either from your IP,
either from your FROM field or both.
