it's pretty normal: during feeding of the protocol, a new route can appear
which will be announced normally and then repeated by the feeding process.
if (new) {
struct rip_entry *e;
+#if 0
+ /* This can happen since feeding of protocols is asynchronous */
if (fib_find( &P->rtable, &net->n.prefix, net->n.pxlen ))
log( L_BUG "Inserting entry which is already there?" );
+#endif
e = fib_get( &P->rtable, &net->n.prefix, net->n.pxlen );
e->nexthop = new->attrs->gw;