Back in December 2007 I posted an article on changing the default VPN gateway in OS X to allow you to access the internet whilst being connected to a internet restricted VPN connection. This, however doesn't work for some OS X Leopard users (including myself) and you still cannot access the internet whilst connected to a VPN connection no matter what you do.

Well after some playing around, I managed to get this all working fine in Leopard by making a small (and simple) change. So if you cannot access the internet whilst connected to some VPN connections in Leopard then try the following:

1. Firstly, you need to find your DNS server, to do this open up System Preferences > Network and find the DNS server for your internet connection. So in my case, I select "Ethernet 1" and I will see my DNS server as 192.168.0.1
2. Whilst still in Network, select the VPN connection you want to "fix" and click "Advanced". Under the "DNS" option, enter the DNS server you got from point 1 (in my case 192.168.0.1).
3. Before leaving this area, select the "Options" tab and ensure the "Send all traffic over the VPN connection" checkbox is not ticked.

Now close the System Preferences window and connect to you VPN connection, and hopefully you will be able to access the internet still... it works a treat for me!