--- common/net_udp.c.orig	Tue Jun 22 10:54:05 1999
+++ common/net_udp.c	Mon Jan 24 17:14:12 2000
@@ -335,6 +335,10 @@
              }
         }
 
+#ifndef IPV6_ADD_MEMBERSHIP
+#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
+#endif
+
 	if (IN6_IS_ADDR_MULTICAST(&(s->addr6))) {
 		unsigned int      loop = 1;
 		struct ipv6_mreq  imr;