[Samba] net ads keytab add has no visible effects

[Maciej Piechotka]

When I issue command 'net ads keytab add HTTP' I got a message
'Processing principals to add...' but nothing else happens - no change
in keytab, net ads keytab list output, no errors in log etc.

[Global]
  netbios name = HOSTNAME
  workgroup = DOMAIN
  realm = DOMAIN
  server string = %h Gentoo DT
  security = ads
  auth methods = sam winbind
  encrypt passwords = yes
  kerberos method = system keytab

  preferred master = no
  dns proxy = no
  wins support = no

  inherit acls = Yes
  map acl inherit = Yes
  acl group control = yes

  load printers = no
  debug level = 3
  use sendfile = no

  log level = 10

  strict allocate = yes

  acl allow execute always = True
  username map = /etc/samba/usermap.txt


[libdefaults]
        default_realm   =       DOMAIN
        clockskew       =       300
        ticket_lifetime =       3d
        renew_lifetime  =       7d
        forwardable     =       true
        proxiable       =       true
        dns_lookup_realm =      true
        dns_lookup_kdc  =       true

[realms]
        DOMAIN = {
                default_domain = DOMAIN
                auth_to_local = RULE:[1:$1@$0](^.*@DOMAIN$)s/@DOMAIN/@domain/
        }

[domain_realm]
        .kerberos.server = DOMAIN
        .domain = DOMAIN
        domain = DOMAIN

[appdefaults]
        pam = {
        ticket_lifetime         = 1d
        renew_lifetime          = 1d
        forwardable             = true
        proxiable               = false
        retain_after_close      = false
        minimum_uid             = 0
        debug                   = false
        }

[logging]
        default                 = FILE:/var/log/krb5libs.log
        kdc                     = FILE:/var/log/kdc.log
        admin_server            = FILE:/var/log/kadmind.log

Any idea what may be wrong?