ADDING DRIVES TO A RAID 5 CONFIGURATION

Good afternoon,
I need to add 4 additional 18.2Gb drives to an ES40 running TRU64 v5.1A.
Controller KZPCC-CE with RAID 5 configuration.
I am not running AdvFS

My question is:  Is there any way to add the 4 drives to the RAID configuration without having to reconfigure the entire system,  re-install the OS and then restore all of the data?

My thought is that I will have to rebuild the RAID configuration after I add the 4 additional drives and this will wipe out the OS and data on the existing drives.

The run bios pza0  shows:
#0  PM3755U2B
             BUS 0       0,0
                             0,1
                             0,2
                             0,3
             BUS 1        1,0
                              1,1
                              1,2
                              1,3
            BUS 2 0,0,0,0 RAID5
                                     0,1
                                      0,2
                                       0,3
                                      1,0

             0,1,1,0 Hotspare
                                    1,1
             0,1,2,0 Hotspare
                                     1,2
             0,1,3,0 Hotspare
                                      1,3

Any thoughts are appreciated.

Thanks



Jane Caldwell-Myers
Computing & Telecommunications
Laurentian University
705 675-1151 ext 2150