Comment 4 for bug 280160

When the up script is called at restart, openvpn doesn't set ifconfig_remote, route_gateway_1, ifconfig_local, route_network_1, route_net_gateway, route_vpn_gateway and route_netmask_1, resulting in nm-openvpn-service-openvpn-helper failing.

I've submitted this upstream as :
http://bugzilla.gnome.org/show_bug.cgi?id=556134

One way for us around it is to disable the --up-restart parameter call in src/nm-openvpn-service.c, though the proper fix is probably to make n-m-openvpn use the old values if none are set by the --up-restart script call...