zfs discuss - Mar 2010 - Question: zfs set userquota not working on existing datasets

Greetings all,

I recently applied all patches and upgraded my zpool to version 15 
and zfs to version 4 so I could start using the zfs userquota 
feature. What I''ve found though is that I can only apply them on new 
datasets, not on the existing datasets. Here is an example:

# zfs list
NAME   USED  AVAIL  REFER  MOUNTPOINT
data  50.7G   145G  50.7G  /data
# zpool upgrade
This system is currently running ZFS pool version 15.

All pools are formatted using this version.
# zfs upgrade
This system is currently running ZFS filesystem version 4.

All filesystems are formatted with the current version.
# zfs set userquota at user1=50G data
# zfs get userquota at user1 data
NAME  PROPERTY           VALUE              SOURCE
data  userquota at user1    -                  -
# zfs create data/test
# zfs set userquota at user1=50G data/test
# zfs get userquota at user1 data/test
NAME       PROPERTY           VALUE              SOURCE
data/test  userquota at user1  50G                local

Anyone have an idea of a fix, please? Or is this a known limitation?

Many thanks,
Tim