Since Solaris 10u4 we have seen a new behavior when trying to activate mpxio.

First you need to activate mpxio which is by default disabled:

vi /kernel/drv/fp.conf
mpxio-disable="no";

After a reboot, the disks that was there, simply disappear, a luxadm -e forcelip device does not solve the issue.

But the old disks command do the trick:
EDIT: Toots told us that in fact disks is a hard link to devfsadm, which is true

# format
Searching for disks...done


AVAILABLE DISK SELECTIONS:
       0. c1t0d0 <LSILOGIC-LogicalVolume-3000 cyl 65533 alt 2 hd 16 sec 136>
          /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/sd@0,0
Specify disk (enter its number): ^C

# disks

# format
Searching for disks...done

c4t60060E8004F259000000F2590000321Ad0: configured with capacity of 49.99GB
c4t60060E8004F259000000F25900003216d0: configured with capacity of 49.99GB
c4t60060E8004F259000000F25900000201d0: configured with capacity of 1.99GB
c4t60060E8004F259000000F25900003217d0: configured with capacity of 49.99GB
c4t60060E8004F259000000F25900003219d0: configured with capacity of 49.99GB
c4t60060E8004F259000000F25900003218d0: configured with capacity of 49.99GB
c4t60060E8004F259000000F25900000200d0: configured with capacity of 1.99GB


AVAILABLE DISK SELECTIONS:
       0. c1t0d0 <LSILOGIC-LogicalVolume-3000 cyl 65533 alt 2 hd 16 sec 136>
          /pci@7c0/pci@0/pci@1/pci@0,2/LSILogic,sas@2/sd@0,0
       1. c4t60060E8004F259000000F2590000321Ad0 <HITACHI-OPEN-V-SUN-5008 cyl 13651 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f2590000321a
       2. c4t60060E8004F259000000F25900003216d0 <HITACHI-OPEN-V-SUN-5008 cyl 13651 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900003216
       3. c4t60060E8004F259000000F25900000201d0 <HITACHI-OPEN-V-SUN-5008 cyl 544 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900000201
       4. c4t60060E8004F259000000F25900003217d0 <HITACHI-OPEN-V-SUN-5008 cyl 13651 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900003217
       5. c4t60060E8004F259000000F25900003219d0 <HITACHI-OPEN-V-SUN-5008 cyl 13651 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900003219
       6. c4t60060E8004F259000000F25900003218d0 <HITACHI-OPEN-V-SUN-5008 cyl 13651 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900003218
       7. c4t60060E8004F259000000F25900000200d0 <HITACHI-OPEN-V-SUN-5008 cyl 544 alt 2 hd 15 sec 512>
          /scsi_vhci/ssd@g60060e8004f259000000f25900000200
Specify disk (enter its number): ^C