[Samba] Samba4 DC with 2003 domain in w2k foresta level

[Matteo Cangi]

hi all,
i've added a samba4 additional dc to my domain.
all provision was ok with samba-tool domain join xx.mydomain.com DC
-Uadministrator --realm=xx.mydomain.com command and i can replicate
correctly from winpdc to sambadc.
i have a couple of questions:
1) with adsedit i see objectversion 47 for my winpdc.mydom.com (is w2k3)
which means 2008R2 (correct?)
2) on the samba4 side if i test samba-tool domain level show i have an
error Could not retrieve the actual domain, forest level and/or lowest DC
function level!
from the ad user and computer mmc a can see that my w2k3 dc are:
DCTYPE GC, DCVERSION W2K3 and my s4dc is DCTYPE GC, DCVERSION W2K
I cannot connect to dns mmc for samba4dc because an error.
Do i have to raise funtional level to w2k3 or w2k8r2 (as objectversion 47
say) of my samba4 dc ? does this action impact to the samba side only ?
thanks in advance for any help