This is in response to a question that was posted in the SUN Solaris Experts group on LinkedIn:
I keep running into people who think that you have to reboot a non-global zone to add a ZFS mountpoint. Not true.
After you add the zfs resource to your zone.xml (use zonecfg, if you follow recomendation, heh) you perform the following on the Global Zone (not within the non-global zone). Be sure to define the type as "legacy":
root@global-zone# mount -F zfs your_zpool/your_filesystem_name /zones/non_global_zonename/root/your_mountpoint
Log into your zone and you should now see the new filesystem (DF or whatever).