I have setup pptpd as my VPN server on Ubuntu Server 9.04, I am able to connect to the VPN from the client and can access the server's local network, but I am unable to connect to the external network via the VPN.

If I login to the server via SSH:

$ ping google.com
PING google.com (74.125.67.100) 56(84) bytes of data.
64 bytes from gw-in-f100.google.com (74.125.67.100): icmp_seq=1 ttl=49 time=65.9 ms
64 bytes from gw-in-f100.google.com (74.125.67.100): icmp_seq=2 ttl=49 time=63.2 ms
64 bytes from gw-in-f100.google.com (74.125.67.100): icmp_seq=3 ttl=49 time=63.9 ms
64 bytes from gw-in-f100.google.com (74.125.67.100): icmp_seq=4 ttl=49 time=66.0 ms

If I connect to the VPN and ping locally:

$ ping google.com
ping: cannot resolve google.com: Unknown host

I have a feeling it is some routing issue on the server but I am unsure.