diff --git a/net/ndisc6/Makefile b/net/ndisc6/Makefile
index f34cd1bf917f..ca3aa2a0e8dd 100644
--- a/net/ndisc6/Makefile
+++ b/net/ndisc6/Makefile
@@ -16,10 +16,17 @@ MAINTAINER=	m.tsatsenko@gmail.com
 COMMENT=	IPv6 network diagnostic tools
 
 LICENSE=	GPLv2
+
 USE_BZIP2=	yes
 GNU_CONFIGURE=	yes
 CONFIGURE_ARGS=	--disable-suid-install
 
+.include <bsd.port.pre.mk>
+
+.if ${OSVERSION} >= 900000
+EXTRA_PATCHES+=	${FILESDIR}/extra-patch-rdnssd-rdnssd.h
+.endif
+
 .if !defined(WITHOUT_NLS)
 USE_GETTEXT=	yes
 .else
@@ -43,4 +50,4 @@ post-install:
 .endfor
 .endif
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>
diff --git a/net/ndisc6/files/extra-patch-rdnssd-rdnssd.h b/net/ndisc6/files/extra-patch-rdnssd-rdnssd.h
new file mode 100644
index 000000000000..1aa03c3104b9
--- /dev/null
+++ b/net/ndisc6/files/extra-patch-rdnssd-rdnssd.h
@@ -0,0 +1,18 @@
+--- rdnssd/rdnssd.h.orig    2011-07-23 01:03:38.000000000 +0400
++++ rdnssd/rdnssd.h 2011-07-23 01:03:56.000000000 +0400
+@@ -32,15 +32,6 @@
+ /* Belongs in <netinet/icmp6.h> */
+ #define ND_OPT_RDNSS 25
+ 
+-struct nd_opt_rdnss
+-{
+-	uint8_t nd_opt_rdnss_type;
+-	uint8_t nd_opt_rdnss_len;
+-	uint16_t nd_opt_rdnss_resserved1;
+-	uint32_t nd_opt_rdnss_lifetime;
+-	/* followed by one or more IPv6 addresses */
+-};
+-
+ # ifdef __cplusplus
+ extern "C" {
+ # endif