postfix/smtp[4920]: AD1B357C1: to=<zzzzzz@yahoo.co.jp>, orig_to=<root>, relay=smtp.xxxx.ne.jp[xx.xx.xx.xx]:25, delay=0.26, delays=0.01/0.03/0.17/0.05, dsn=5.0.0, status=bounced (host smtp.xxxx.ne.jp[xx.xx.xx.xx] said: 553 myhost123.xxxx.ne.jp does not exist (in reply to MAIL FROM command))