diff --git a/include/zmq.h b/include/zmq.h
index e349f9c5..9678b870 100644
--- a/include/zmq.h
+++ b/include/zmq.h
@@ -261,6 +261,7 @@ ZMQ_EXPORT int zmq_msg_set (zmq_msg_t *msg, int option, int optval);
 
 /*  Deprecated aliases                                                        */
 #define ZMQ_NOBLOCK ZMQ_DONTWAIT
+#define ZMQ_FAIL_UNROUTABLE ZMQ_ROUTER_MANDATORY
 #define ZMQ_ROUTER_BEHAVIOR ZMQ_ROUTER_MANDATORY
 
 /******************************************************************************/