I have been using my netbsd-current 486 as a gateway between one
ethernet and a PPP link (I did SLIP previously too) for months.
I'm running gated (from 2.1) NetBSD version: 1.1.1.1, not routed.
But I never tried routed; it might work.
Here is my /etc/gated.conf:

rip yes;
hello no;

My ifconfig looks like this (I am using PPP right now; SLIP worked
fine too last time I tried it):

ed0: flags=8863<UP,BROADCAST,NOTRAILERS,RUNNING,SIMPLEX,MULTICAST>
	inet 128.52.23.2 netmask 0xffffff00 broadcast 128.52.23.0
lo0: flags=8009<UP,LOOPBACK,MULTICAST>
	inet 127.0.0.1 netmask 0xff000000 
sl0: flags=c010<POINTOPOINT,LINK2,MULTICAST>
ppp0: flags=51<UP,POINTOPOINT,RUNNING>
	inet 128.52.23.2 --> 128.52.32.46 netmask 0xffffff00 

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