|You need to install a driver for the cable modem first.|
Have you got a drivers CD for the cable modem?
Otherwise, the esiest and more secure way is, to put a router between your Thinkpad and the modem.
In that case, you don't have to install an additional driver and you are more secure, because the current routers do have a build in firewall.
The original poster should always write the last response !!!
Let us know, if the problem is solved !!!