Host hangs when new disks are added to 3310

I have a 3310 which came with 5disks and connected to a V480(Solaris 9).I want to fill up the slot with 7disks.But each time I add these disks,the host hangs but if I remove them,the host goes back to normal.Has anybody come across this kind of situation.?Any ideas?.
[281 byte] By [joebenm] at [2007-11-25 23:03:57]
# 1
Are you adding the disks while the Sun server is online? How are the existing disks organized? Have you tried turning the server off and using the serial console of your RAID for configuring your disks?
bdraschk at 2007-7-5 17:55:42 > top of Java-index,Storage Forums,Storage General Discussion...
# 2
The existing disks are JBOD RAID 5.I have tried adding these disk while the server was online and as well as offline,and the system still hung.
joebenm at 2007-7-5 17:55:42 > top of Java-index,Storage Forums,Storage General Discussion...