On Solaris 10 boxes, after a reboot, all submirrors "need maintenance". A metasync immediately clears the problem but the system will be back in "need maintenance" state right after a reboot.
Resolution
Verify that we have a problem because mdmonitor is offline,
svcs | grep mdmonitor offline 2009 svc:/system/mdmonitor:default
Fix the problem,
svcadm disable rpc/bind svcadm disable rpc/meta svcadm enable system/mdmonitor
Details
http://www.thatsjava.com/java-enterprise/60195/
http://www.sunmanagers.org/pipermail/summaries/2005-June/006531.html