[Samba] Samba4 DNS - Adding MX record

[Ринат]

I'm using samba 4.1.0pre1-GIT-bcacd8f provisioned to use the internal dns server. On Ubuntu 12.04 server 64 bit.
I need to add  MX record.
network 192.168.1.0/24
domain controller: dc.fond.ru (192.168.1.100)
zone name: fond.ru
mail server: zimbra.fond.ru (192.168.1.104)

I add A record:
./samba-tool dns add dc fond.ru zimbra A 192.168.1.104

Query:
./samba-tool dns query dc fond.ru zimbra A
   Name=, Records=1, Children=0
     A: 192.168.1.104 (flags=f0, serial=2, ttl=900)

and host -t A zimbra.fond.ru.returns:
zimbra.fond.ru has address 192.168.1.104

Good! But:

Add MX record:
./samba-tool dns add dc fond.ru zimbra MX 'zimbra.fond.ru 10'

Query:
./samba-tool dns query dc fond.ru zimbra MX
   Name=, Records=2, Children=0
     MX: zimbra.fond.ru. (10) (flags=f0, serial=3, ttl=900)

but host -t MX fond.ru. returns:
Host fond.ru. not found: 3(NXDOMAIN)


I may be  wrong to  add the  MX record?