Are you running slip? The default route is set in /etc/init.d/network The other routes will also be added from that file. Kernel 2.2.x automatically adds a route for each interface when it is activated.
I use diald which creates a slip device to act as a proxy for the ppp connection. When traffic is detected on the slip interface (sl0 on my machine) diald starts dialing the modem and on connect starts ppp. My routing table looks similar to the one you posted when I'm not connected to my isp. Pat --- Signature removed because some people are way too thin skinned
