User-Agent:       Mozilla/5.0 (X11; Linux x86_64; rv:35.0) Gecko/20100101
Firefox/35.0
Build Identifier: 

C function:
void register_to_dbus(DBusConnection *bus_connection)
{
  int error = 0;
  DBusMessage *msg;
  DBusPendingCall *pending;
  DBusError bus_error;

  msg = dbus_message_new_method_call("org.freedesktop.NetworkManager",
      "/org/freedesktop/NetworkManagter/AgentManager",
"org.freedesktop.NetworkManager.AgentManager",
      "Register"
    );

  dbus_error_init(&bus_error);

  dbus_message_append_args(msg, DBUS_TYPE_STRING, &service_name,
DBUS_TYPE_INVALID); 

  if (!dbus_connection_send_with_reply_and_block(bus_connection, msg, -1,
&bus_error)) {

      puts("ERROR2");  
    }

    if (dbus_error_is_set(&bus_error)) {

      printf("Error \"%s\"\n", bus_error.message);
    }
    if (0 == pending) {

      puts("ERROR3");  
    }

    dbus_connection_flush(bus_connection);
}

Gives output:
ERROR2
Error "Method "Register" with signature "s" on interface
"org.freedesktop.NetworkManager.AgentManager" doesn't exist
"

But KDE keyring manager works fine with NetworkManager.
I use Tumbleweed, but on 13.2 the same error ocurs

Reproducible: Always

Actual Results:  
Console output:
ERROR2
Error "Method "Register" with signature "s" on interface
"org.freedesktop.NetworkManager.AgentManager" doesn't exist
"


Expected Results:  
My own keyring iks registered to NetworkManager  SecretApi via DBus.