openvpn server starting error

[umbekannt]

Hello guys,
i've installed a openvpn server on my vps with this tutorial:
http://docs.openvpn.net/how-to-tutorial ... -debian-6/

So i logged in in my openvpn adminpanel and want to start the server, but the server giving me an error:

Error:

iptables service not started because of error (SVC_RUN_EXCEPT)

Anyone knows a solution for this problem?

Tun/TAP device is on.