2007-08-15:

I recently created a stripe using ZFS over several disks, and after one disk failed, I decided to go grab a new disk
and then create a couple of mirrors instead.
Problem is, when trying to "equalize" all drives, I found several issues: 

1. the disk types were not matching:

       1. c0t2d0 <FUJITSU-MAV2073RCSUN72G-0301-68.37GB>
          /pci@0,0/pci1022,7450@2/pci1000,3060@3/sd@2,0
       2. c0t3d0 <DEFAULT cyl 8921 alt 2 hd 255 sec 63>
          /pci@0,0/pci1022,7450@2/pci1000,3060@3/sd@3,0

I could not get the drive 1, out of its FUJITSU-MAV2073RCSUN72G-0301-68.37GB type !, dang. The desired type was DEFAULT, which is shown in c0t3,
 and I tried hard to set that using the format command, but I found that it was failing 
always after asking me the Maximum number of LBA's.  (good thing it didn't ask me for the max number of LGM's else I'd chuck the server out the window)
Anyway, after fdisking, I found that the disks I used on the ZFS decided to label themselves as EFI,
check this:
type format,

2. then type fdisk, and you see:
             Total disk size is 8924 cylinders
             Cylinder size is 16065 (512 byte) blocks

                                               Cylinders
      Partition   Status    Type          Start   End   Length    %
      =========   ======    ============  =====   ===   ======   ===
          1                 EFI               0  8921    8922    100


... and after repeated attempts to erase the partition, using format, the thing was still there. , 
and forget trying to delete "partition 8" the one for the reserved cyls.  
I even tried to dd , from the c0t3 drive to the c0t2, into p0 (without results), and into s2, which gave me I/O error.




SOLUTION:
So, the trick consisted of executing "format -e" , which can obviously handle these EFI disks. And my desire was to convert the disk back to type "SMI".
So, after fdisking, and deleting the partition. I relabled the disk, and quit format.
Then I re-executed format (without -e), and voilla, I found an empty fdisk partition table, and then created the SOLARIS2 partition 100%, 
and then the subpartitions did not show partition 8 anymore, and all was back to "normal".

I will now grab the 2 disks, c0t3, and c0t2, and make a ZFS mirror. 
Only shog knows what the disk vtocs will look after, but I don't care, at least now I am putting apples with apples into the burner.