Index: trunk/src_plugins/autoroute/autoroute.c
===================================================================
--- trunk/src_plugins/autoroute/autoroute.c	(revision 31549)
+++ trunk/src_plugins/autoroute/autoroute.c	(revision 31550)
@@ -4707,7 +4707,7 @@
 				PCB_FLAG_ASSIGN(PCB_FLAG_SELECTED, rnd_true, line);
 				pcb_rat_invalidate_draw(line, 0);
 #endif /* DEBUG_STALE_RATS */
-				rnd_message(RND_MSG_ERROR, "The rats nest is stale! Aborting autoroute...\n");
+				rnd_message(RND_MSG_ERROR, "The rats nest is stale! Aborting autoroute...\nNOTE: you need to use the autoroute-specific rats\n the usual rats optimization won't work (check in the menu)!\n");
 				goto donerouting;
 			}
 			/* merge subnets into a net! */