毎晩今くらいに出るんだけどコレ、なんとかならないかな。

localhost sendmail: My unqualified host name (localhost) unknown; sleeping for retry
localhost sendmail: unable to qualify my own domain name (localhost) -- using short name
localhost sendmail: NOQUEUE: SYSERR(root): /etc/mail/sendmail.cf: line 81: fileclass: cannot open /etc/mail/local-host-names: Group writable directory