(급!!)BOGUS. 화일이 자꾸 만들어져요..

       If /var/spool/mail/$LOGNAME is a bogus mailbox (i.e. does  not  belong  to
       the recipient, is unwritable, is a symbolic link or is a hard link), proc-
       mail will upon startup try to rename it into a  file  starting  with 
      `BOGUS.$LOGNAME.' and ending in an inode-sequence-code.  If this turns out to
       be impossible, ORGMAIL will have no initial value, and hence will  inhibit
       delivery without a proper rcfile.

       If  /var/spool/mail/$LOGNAME  already  is a valid mailbox, but has got too
       loose permissions on it, procmail will correct this.  To prevent  procmail
       from doing this make sure the u+x bit is set.

      $LOGNAME 은 파일명이고 rcfile 은 $HOME/.procmailrc 이며
      ORGMAIL 은 /var/spool/mail/$LOGNAME 입니다.

      uid가 변경되었다거나 유저가 삭제되고 파일만 남았을 경우
      위 파일이 생성되는 것 같군요.