I have installed openvpn, and checked that it properly authenticates and established a VPN connection. The tun interface and pushed static routes are all properly updated. (I verify these with ifconfig and netstat -nr). They appear on the N900 just as they do on my mac after establishing the VPN tunnel.

Unfortunately, the VPN traffic on the N900 does not 'pass though' the VPN tunnel. I cant get to hosts in the remote net, despite the routing entries on the N900 looking perfect after establishing the VPN. Cant ping the tun0 IP address or even any remote host.

What is happening? Where should I start looking?