Migrating a UFS system with non global zone to ZFS

Hi ,
we have a T5240 system which is now under ufs . The root and other non root file systems are also in ufs.
Now /usr is almost 95% utilized and is being used by non global zones. It is a solaris9 branded zone.
We cannot increase the size of this file system. So I am planning to migrate the entire system to zfs.

root@ldevhost# zoneadm list -cv
  ID NAME             STATUS     PATH                           BRAND    IP
   0 global           running    /                              native   shared
   1 solhot9          running    /zones/solhot9                 solaris9 shared
root@ldevhost#
root@ldevhost # df -h /zones
Filesystem             size   used  avail capacity  Mounted on
/dev/dsk/c1t0d0s3       20G   3.6G    16G    19%    /zones