<username removed of course>@optus.com.au
Technical details of permanent failure:
Google tried to deliver your message, but it was rejected by the
recipient domain. We recommend contacting the other email provider for
further information about the cause of this error. The error that the
other server returned was: 550 550 5.7.1 Inappropriate language
used:SHIT (state 18)."
I wonder if Telstra do the same to their work emails.