Index: classlib/modules/portlib/src/main/native/include/unix/hysock.h =================================================================== --- classlib/modules/portlib/src/main/native/include/unix/hysock.h (revision 964795) +++ classlib/modules/portlib/src/main/native/include/unix/hysock.h (working copy) @@ -127,7 +127,7 @@ #define OS_MCAST_LOOP IP_MULTICAST_LOOP #if defined(IPv6_FUNCTION_SUPPORT) #define OS_MCAST_INTERFACE_2 IPV6_MULTICAST_IF -#if defined(FREEBSD) || defined(MACOSX) +#if defined(FREEBSD) || defined(MACOSX) || defined(ZOS) #define OS_IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP #define OS_IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP #else