This fix does not work. That only comes into play when the machine has no network connection at all - it decides which one to try first based on the order in that dialog. There are some apps out there that allow you to start a PPTP connection (PiePants and DigiTunnel, among others) but none of them appears to work with Jaguar (10.2)... so I am stuck. There is a built-in pptp client in Jaguar, which connects fine but doesn't have an option to disable default route. I have tried the following (in a terminal window)
sudo route delete default
sudo route add default [ip of real gateway here]
And that appears to work, but after a few minutes it stops working and I have to disconnect the pptp connection in order to get internet again. Any clues?