--- src/sys/netinet/ip_var.h	2006/09/30 21:23:28	1.20
+++ src/sys/netinet/ip_var.h	2007/08/16 20:03:57	1.21
@@ -115,6 +115,7 @@ struct ip_moptions {
 	u_char	imo_multicast_ttl;	/* TTL for outgoing multicasts */
 	u_char	imo_multicast_loop;	/* 1 => hear sends if a member */
 	u_short	imo_num_memberships;	/* no. memberships this socket */
+	u_short imo_max_memberships;    /* max memberships this socket */
 	struct	in_multi *imo_membership[IP_MAX_MEMBERSHIPS];
 	u_long	imo_multicast_vif;	/* vif num outgoing multicasts */
 };