ZFSv28, zfs list behaviour and sysutils/freebsd-snapshot

Hi,

I'm using sysutils/freebsd-snapshot to make periodic ZFS backup snapshot
and this soft is broken since the upgrade of my pool to ZFSv28.
After some debugging it appears that "zfs list" behaviour has changed
with ZFSv28, and since freebsd-snapshot relies on "zfs list" to retrieve
the "ZFS file system name" from the "mountpoint name" the soft doesn't
work anymore.

output of "zfs list" on a 8.2R amd64 (ZFSv15) :
zfs list /home/murankar
NAME                 USED  AVAIL  REFER  MOUNTPOINT
tank/home/murankar  1.47M  1.59T  1.47M  /home/murankar

zfs list tank/home/murankar
NAME                 USED  AVAIL  REFER  MOUNTPOINT
tank/home/murankar  1.47M  1.59T  1.47M  /home/murankar

on a 9-Current amd64 I've got no output for "zfs list /home/murankar"
and a exit code of 1
the output of "zfs list tank/home/murankar" is correct :
NAME                 USED  AVAIL  REFER  MOUNTPOINT
tank/home/murankar  6,56G   286G  6,55G  /home/murankar

Is it the normal behaviour for ZFSv28 or some kind of regression ?

TIA,
Mikaël