I am going to make a determined effort to get my ADSL modem working in Linux. The first thing to do is to move to a kernel later than 2.6.10, since this is the version with which the AccessRunner driver is supposed to work. I therefore downloaded the latest kernel sources and set about compiling them. The compilation was a very straightforward process; just a question of a few configure and make commands, and adding entries to grub's menu.lst. The only catch is that you need gcc 2.95 for the compilation. Now I have the option of booting with either 126.96.36.199 or Suse's default, 2.6.5-7.
There was one problem with running 188.8.131.52, though. The first boot didn't allow me to connect to my Windows machine, though the network interfaces appeared OK. This got sorted out by iteself on a reboot.