maillog에서 오류가나는데요 ..급해요 도와주세요

Jul 21 16:14:16 www sendmail[14248]: dangerous permissions=40777 on queue directory /var/spool/clientmqueue/
Jul 21 16:14:16 www sendmail[14248]: k6L7EG3O014248: from=nobody, size=20328, class=0, nrcpts=1, msgid=<200607210714.k6L7EG3O014248@www.kll.co.kr>, relay=nobody@localhost
Jul 21 16:14:16 www sendmail[14250]: k6L7EGrk014250: SYSERR(root): collect: Cannot write ./dfk6L7EGrk014250 (sm_io_flush||sm_io_error, uid=0, gid=51): Input/output error
Jul 21 16:14:16 www sendmail[14250]: k6L7EGrk014250: from=<nobody@www.kll.co.kr>, size=20562, class=0, nrcpts=1, proto=ESMTP, daemon=MTA, relay=localhost [127.0.0.1] (may be forged)
Jul 21 16:14:16 www sendmail[14248]: k6L7EG3O014248: to=377377377377377377377377377377377377377377 <kyo8017@nate.com> , ctladdr=nobody (99/99), delay=00:00:00, xdelay=00:00:00, mailer=relay, pri=30200, relay=[127.0.0.1] [127.0.0.1], dsn=4.0.0, stat=Deferred: 421 4.3.0 collect: Cannot write ./dfk6L7EGrk014250 (sm_io_flush||sm_io_error, uid=0, gid=51): Input/output error

도와주세요 이런에러가나는데  도대체 왜이런에러가나는지모르겠네요