Comment 2 for bug 465736

I ran into the same problem trying to setup the shrewsoft VPN client for the linux boxes at our office. Since the shrewsoft client isn't as popular as vpnc, it took quite a bit of googling to find the solution. Would be nice to see this package fixed soon, especially since vpnc has a phase 2 re-keying issue that causes our clients to drop the connection every few hours (http://www.gossamer-threads.com/lists/vpnc/devel/3246, ).

(some breadcrumbs for any other folks googling for this solution)
* Read this bug description if you are running into the following problems *
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Ubuntu shrewsoft client connects but no traffic goes over the tunnel
Ubuntu shrewsoft client connects, can ping VPN gateway but no systems over the tunnel
Ubuntu shrewsoft client says 'tunnel enabled' but cannot ping VPN hosts
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