diff --git a/newlib/libc/sys/rtems/include/netinet6/in6.h b/newlib/libc/sys/rtems/include/netinet6/in6.h
index 99ac803b8..37e1e93c0 100644
--- a/newlib/libc/sys/rtems/include/netinet6/in6.h
+++ b/newlib/libc/sys/rtems/include/netinet6/in6.h
@@ -658,6 +658,7 @@ struct ip6_mtuinfo {
 #define	M_LOOP			M_PROTO6
 #define	M_AUTHIPDGM		M_PROTO7
 #define	M_RTALERT_MLD		M_PROTO8
+#define	M_FRAGMENTED		M_PROTO9	/* contained fragment header */
 
 #ifdef _KERNEL
 struct cmsghdr;