I had to revisit that post and change the IP address again today, after having bought a new router with a new LAN configuration.
Here is the how-to for specifying an explicit DNS server, to guarantee that the Ubuntu SSH server will have Internet as well.
Edit this file in the terminal:
sudo nano etc/dhcp3/dhclient.conf
Changes:
1. Remove the "domain-name-servers" from the request directive.
2. Modify the line:
prepend domain-name-servers 127.0.0.1;by changing 127.0.0.1 to the DNS server of your Internet connection.
For my case, using Sun Broadband (Huawei usb modem), it was:
prepend domain-name-servers 202.138.128.50,202.138.128.54;
Taken from this Ubuntu Forum thread.