为什么root给自己发信？

jamwolf

Maillog的部分内容：

Sep 10 09:35:04 AirTravel sendmail[7548]: i8A1Z4I7007548: from=root, size=266, class=0, nrcpts=1, msgid=<200409100135.i8A1Z4I7007548@localhost.localdomain>;, relay=root@localhost
Sep 10 09:35:04 AirTravel postfix/smtpd[7549]: connect from AirTravel[127.0.0.1]
Sep 10 09:35:04 AirTravel postfix/smtpd[7549]: 893BA291A0: client=AirTravel[127.0.0.1]
Sep 10 09:35:04 AirTravel postfix/smtpd[7549]: 893BA291A0: reject: RCPT from AirTravel[127.0.0.1]: 554 <root@localhost.localdomain>;: Recipient address rejected: Access denied; from=<root@localhost.localdomain>; to=<root@localhost.localdomain>; proto=ESMTP helo=<localhost.localdomain>;
Sep 10 09:35:05 AirTravel sendmail[7548]: i8A1Z4I7007548: to=root, ctladdr=root (0/0), delay=00:00:01, xdelay=00:00:01, mailer=relay, pri=30266, relay=[127.0.0.1] [127.0.0.1], dsn=5.0.0, stat=Service unavailable
Sep 10 09:35:06 AirTravel sendmail[7548]: i8A1Z4I7007548: i8A1Z4I8007548: DSN: Service unavailable
Sep 10 09:35:06 AirTravel postfix/smtpd[7549]: 8D03F291A0: client=AirTravel[127.0.0.1]
Sep 10 09:35:06 AirTravel postfix/smtpd[7549]: 8D03F291A0: reject: RCPT from AirTravel[127.0.0.1]: 554 <root@localhost.localdomain>;: Recipient address rejected: Access denied; from=<>; to=<root@localhost.localdomain>; proto=ESMTP helo=<localhost.localdomain>;
Sep 10 09:35:07 AirTravel sendmail[7548]: i8A1Z4I8007548: to=root, delay=00:00:01, xdelay=00:00:01, mailer=relay, pri=31290, relay=[127.0.0.1] [127.0.0.1], dsn=5.0.0, stat=Service unavailable
Sep 10 09:35:08 AirTravel sendmail[7548]: i8A1Z4I8007548: i8A1Z4I9007548: return to sender: Service unavailable
Sep 10 09:35:08 AirTravel postfix/smtpd[7549]: 905A9291A0: client=AirTravel[127.0.0.1]
Sep 10 09:35:08 AirTravel postfix/smtpd[7549]: 905A9291A0: reject: RCPT from AirTravel[127.0.0.1]: 554 <postmaster@localhost.localdomain>;: Recipient address rejected: Access denied; from=<>; to=<postmaster@localhost.localdomain>; proto=ESMTP helo=<localhost.localdomain>;
Sep 10 09:35:09 AirTravel sendmail[7548]: i8A1Z4I9007548: to=postmaster, delay=00:00:01, xdelay=00:00:01, mailer=relay, pri=32314, relay=[127.0.0.1] [127.0.0.1], dsn=5.0.0, stat=Service unavailable
Sep 10 09:35:10 AirTravel sendmail[7548]: i8A1Z4I8007548: Losing ./qfi8A1Z4I8007548: savemail panic
Sep 10 09:35:10 AirTravel sendmail[7548]: i8A1Z4I8007548: SYSERR(root): savemail: cannot save rejected email anywhere
Sep 10 09:35:10 AirTravel postfix/smtpd[7549]: disconnect from AirTravel[127.0.0.1]

我的系统是Fedora Core 2，邮件系统是自带的Postfix 2.0.18，查看maillog发现每5分钟就有这种情况发生，会产生大量日志，有用的日志都淹没在里面了！能问问高人这是什么原因导致的吗？