scott@fyrenice:~$ exim -v postmaster@fyrenice.com
From: scott@fyrenice.com
To: postmaster@fyrenice.com
Subject: Testing Exim

This is a test message.
LOG: MAIN
  <= scott@fyrenice U=scott P=local S=360
scott@fyrenice:~$ delivering 1QKrOr-0007ZI-GX
R: system_aliases for postmaster@fyrenice.com
R: smarthost for root@fyrenice
T: remote_smtp_smarthost for root@fyrenice
Connecting to smtp.g.comcast.net [76.96.30.117]:25 ... connected
  SMTP<< 220 omta14.emeryville.ca.mail.comcast.net comcast ESMTP server ready
  SMTP>> EHLO fyrenice.com
  SMTP<< 250-omta14.emeryville.ca.mail.comcast.net hello [173.14.239.229], pleased to meet you
         250-HELP
         250-AUTH LOGIN PLAIN
         250-SIZE 15728640
         250-ENHANCEDSTATUSCODES
         250-8BITMIME
         250-STARTTLS
         250 OK
  SMTP>> STARTTLS
  SMTP<< 220 2.0.0 Ready to start TLS
  SMTP>> EHLO fyrenice.com
  SMTP<< 250-omta14.emeryville.ca.mail.comcast.net hello [173.14.239.229], pleased to meet you
         250-HELP
         250-AUTH LOGIN PLAIN
         250-SIZE 15728640
         250-ENHANCEDSTATUSCODES
         250-8BITMIME
         250 OK
  SMTP>> MAIL FROM:<scott@fyrenice> SIZE=1394
scott@fyrenice:~$   SMTP<< 550 5.1.0 <scott@fyrenice> sender rejected : invalid sender domain
  SMTP>> QUIT
LOG: MAIN
  ** root@fyrenice <postmaster@fyrenice.com> R=smarthost T=remote_smtp_smarthost: SMTP error from remote mail server after MAIL FROM:<scott@fyrenice> SIZE=1394: host smtp.g.comcast.net [76.96.30.117]: 550 5.1.0 <scott@fyrenice> sender rejected : invalid sender domain
scott@fyrenice:~$ LOG: MAIN
  <= <> R=1QKrOr-0007ZI-GX U=Debian-exim P=local S=1351
delivering 1QKrPQ-0007ZP-4Q
R: smarthost for scott@fyrenice
scott@fyrenice:~$ LOG: MAIN
  Completed
scott@fyrenice:~$ T: remote_smtp_smarthost for scott@fyrenice
Connecting to smtp.g.comcast.net [76.96.62.117]:25 ... connected
  SMTP<< 220 omta19.westchester.pa.mail.comcast.net comcast ESMTP server ready
  SMTP>> EHLO fyrenice.com
  SMTP<< 250-omta19.westchester.pa.mail.comcast.net hello [173.14.239.229], pleased to meet you
         250-HELP
         250-AUTH LOGIN PLAIN
         250-SIZE 15728640
         250-ENHANCEDSTATUSCODES
         250-8BITMIME
         250-STARTTLS
         250 OK
  SMTP>> STARTTLS
  SMTP<< 220 2.0.0 Ready to start TLS
  SMTP>> EHLO fyrenice.com
  SMTP<< 250-omta19.westchester.pa.mail.comcast.net hello [173.14.239.229], pleased to meet you
         250-HELP
         250-AUTH LOGIN PLAIN
         250-SIZE 15728640
         250-ENHANCEDSTATUSCODES
         250-8BITMIME
         250 OK
  SMTP>> MAIL FROM:<> SIZE=2410
  SMTP<< 250 2.1.0 <> sender ok
  SMTP>> RCPT TO:<scott@fyrenice>
  SMTP<< 550 5.1.1 <scott@fyrenice> recipient invalid domain
  SMTP>> QUIT
LOG: MAIN
  ** scott@fyrenice R=smarthost T=remote_smtp_smarthost: SMTP error from remote mail server after RCPT TO:<scott@fyrenice>: host smtp.g.comcast.net [76.96.62.117]: 550 5.1.1 <scott@fyrenice> recipient invalid domain
LOG: MAIN
  Frozen (delivery error message)

scott@fyrenice:~$ ~