http://www.ubuntu-austria.at/viewtopic.php?t=261 (german) describes a similar problem. Their solution is to explicitly write the mac address of the network card into dhclient.conf .
-- no internet with chello austria cablemodems https://launchpad.net/bugs/83591 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
