> I'm guessing I could probably bypass the check for "same subnet as" if
> the interface is marked IFF_POINTOPOINT (make it deal with the "unnumbered"

I also think you could do.
For mrouted codes, you may want to try like;

--- config.c.orig       Wed Jan 24 21:46:11 1996
+++ config.c    Fri Sep  1 14:53:55 2000
@@ -97,6 +97,9 @@
         * one already installed in the uvifs array.
         */
        for (vifi = 0, v = uvifs; vifi < numvifs; ++vifi, ++v) {
+           /* we don't care about point-to-point links in same subnet */
+           if (flags & IFF_POINTOPOINT)
+               continue;
            if ((addr & v->uv_subnetmask) == v->uv_subnet ||
                (v->uv_subnet & mask) == subnet) {
                system_log(LOG_WARNING, 0, "ignoring %s, same subnet as %s",

> point-to-point interface case), but I'm wondering how IGMP and the multicast
> forwarding code are going to deal with this...

I believe it just works as a normal env.
--
Hitoshi Asaeda