Сбой проверки ipsec в Openswan на & ldquo; Обнаружено два или более интерфейсов, проверяющих переадресацию IP & rdquo;

Я пытаюсь установить L2TP / IPsec VPN. Я установил openswan из репозитория на Ubuntu 13.04

Section: universe/net
Architecture: amd64
Version: 1:2.6.38-1

и настроил его в соответствии с документами сообщества .

# cat /etc/ipsec.conf 
config setup
    nat_traversal=yes
    virtual_private=%v4:10.0.0.0/8,%v4:192.168.0.0/16,%v4:172.16.0.0/12,%v4:!192.168.23.0/24
    oe=off
    protostack=netkey

conn L2TP-PSK-NAT
    rightsubnet=vhost:%priv
    also=L2TP-PSK-noNAT

conn L2TP-PSK-noNAT
    authby=secret
    pfs=no
    auto=add
    keyingtries=3
    rekey=no
    # Apple iOS doesn't send delete notify so we need dead peer detection
    # to detect vanishing clients
    dpddelay=30
    dpdtimeout=120
    dpdaction=clear
    # Set ikelifetime and keylife to same defaults windows has
    ikelifetime=8h
    keylife=1h
    type=transport
    # Replace IP address with your local IP (private, behind NAT IP is okay as well)
    left=my.ip
    # For updated Windows 2000/XP clients,
    # to support old clients as well, use leftprotoport=17/%any
    leftprotoport=17/1701
    right=%any
    rightprotoport=17/%any
    #force all to be nat'ed. because of iOS
    forceencaps=yes

Он запускается нормально, но не проходит проверку

# ipsec verify
Checking your system to see if IPsec got installed and started correctly:
Version check and ipsec on-path                                 [OK]
Linux Openswan U2.6.38/K3.8.0-29-generic (netkey)
Checking for IPsec support in kernel                            [OK]
 SAref kernel support                                           [N/A]
 NETKEY:  Testing XFRM related proc values                      [OK]
[OK]
[OK]
Checking that pluto is running                                  [OK]
 Pluto listening for IKE on udp 500                             [OK]
 Pluto listening for NAT-T on udp 4500                          [OK]
Two or more interfaces found, checking IP forwarding            [FAILED]
Checking NAT and MASQUERADEing                                  [OK]
Checking for 'ip' command                                       [OK]
Checking /bin/sh is not /bin/dash                               [OK]
Checking for 'iptables' command                                 [OK]
Opportunistic Encryption Support                                [DISABLED]

, хотя переадресация, кажется, включена

# cat /proc/sys/net/ipv4/ip_forward
1

Что не так и как мне это сделать это исправить?