cron service is in maintenance state, even all dependent services are online

root@server55 # svcs -a |grep cron

maintenance    23:15:43 svc:/system/cron:default

root@server55 #

root@server55 # svcs -xv cron

svc:/system/cron:default (clock daemon (cron))

State: maintenance since Sun Mar 23 23:15:43 2015

Reason: Start method exited with status 99.

   See: http://sun.com/msg/SMF-8000-KS

   See: man -M /usr/share/man -s 1M cron

   See: man -M /usr/share/man -s 1 crontab

   See: /var/svc/log/system-cron:default.log

Impact: This service is not running.

root@server55 #

root@server55 # svcs -d svc:/system/cron:default

STATE          STIME    FMRI

online         Oct_05   svc:/milestone/name-services:default

online         Oct_05   svc:/system/filesystem/local:default

root@server55