Cannot create ZFS dataset for a zone?

I am trying to get
a solaris8 zone in a solaris 10 box. And am not able to build it:

root@sundev ~> zfs create zonepool/hosts/solaris8test-64
root@sundev ~> zfs set mountpoint=/export/hosts/solaris8test-64
zonepool/hosts/solaris8test-64
root@sundev ~> cp /export/hosts/solaris8/solaris8.zone
/export/hosts/solaris8test-64/solaris8test-64.zone
root@sundev ~> chmod go-rx /export/hosts/solaris8test-*
root@sundev ~> cat /export/hosts/solaris8test-64/solaris8test-64.zone
# Run this file by typing
#  zonecfg -z solaris8test-64 -f 
/export/hosts/solaris8test-64/solaris8test-64.
zone
create -b
set zonepath=/export/hosts/solaris8test-64
set autoboot=true
set ip-type=shared
set brand=solaris8
add fs
set dir=/pub
set special=/export/pub/sol8
set type=lofs
end
add net
set physical=bge0
set address=192.168.11.64
end
root@sundev ~> zonecfg -z solaris8test-64 -f
/export/hosts/solaris8test-64/solaris8test-64.zone
root@sundev ~> zoneadm -z solaris8test-64 install
cannot create ZFS dataset zonepool/hosts/solaris8test-64: dataset already
exists
zoneadm install: error: you must specify an installation source using 
'-a' or
'-d'.
WARNING: Unable to completely remove /export/hosts/solaris8test-64
because it contains additional user data.  Only the standard directory
entries have been removed.
root@sundev ~> zoneadm -z solaris8test-64 list -v
   ID NAME             STATUS     PATH                           BRAND    IP
    - solaris8test-64  configured /export/hosts/solaris8test-64 
solaris8 shared
root@sundev ~>

What is this "cannot create ZFS dataset zonepool/hosts/solaris8test-64:
dataset already exists" trying to tell me? I mean, why would zoneadm 
want to create it to begin with?