[Samba] winbind does not work+sernet package+samba 4.2

[Yanni]

Hello

After failing to join my samba box to winAD 2012, I went and downloaded 
the sernet packages
and samba box join the AD domain using "samba-tool" with no problems.
However I've got problems with winbind.

wbinfo -u returns:

could not obtain winbind interface details: WBC_ERR_WINBIND_NOT_AVAILABLE
could not obtain winbind domain name!
Error looking up domain users

Here is my SMB.CONF
----------------------------------------------------------
[global]
   server string = Samba4 file server
   workgroup = TESTAD
   security = ADS
   realm = TESTAD.BIO.AC.UK


    domain master = no
    prefered master = no
    local master = no
    os level = 0
    browse list = yes


   encrypt passwords = yes
   template shell = /bin/bash
   netbios name = JIMMY
   name resolve order = bcast

   idmap config *:backend = tdb
   idmap config *:range = 2000-3999
   idmap config TESTAD: backend = rid
   idmap config TESTAD: range = 10000-99999


    winbind trusted domains only = no
    winbind use default domain = yes
    winbind enum users = yes
    winbind enum groups = yes
    winbind refresh tickets = Yes
    winbind expand groups = 4
    winbind normalize names = Yes


#Logging Settings
    log level = 3
    log file = /var/log/samba/log.%m
    max log size = 50

[profs]
    comment = WinProfsStorage
    path = /disk1/profs
    read only = no
    store dos attributes = yes
-----------------------------------------------------------------
My /etc/krb5.conf
----------------------------------------------------------------
[logging]
  default = FILE:/var/log/krb5libs.log
  kdc = FILE:/var/log/krb5kdc.log
  admin_server = FILE:/var/log/kadmind.log

[libdefaults]
  dns_lookup_realm = true
  dns_lookup_kdc = true
  ticket_lifetime = 24h
  renew_lifetime = 7d
  forwardable = true
  rdns = false
  default_ccache_name = KEYRING:persistent:%{uid}

[realms]
         TESTAD.BIO.AC.UK = {
                                     kdc = TESTSERVER1.TESTAD.BIO.AC.UK
                                     default_domain = TESTAD.BIO.AC.UK
                                   }

[domain_realm]
              .testad.bio.ac.uk = TESTAD.BIO.AC.UK
              testad.bio.ac.uk = TESTAD.BIO.AC.UK
-------------------------------------------------------------------

Any suggestions, please?

Many thanks for you help