diff --git a/sys/net/if_mpls.c b/sys/net/if_mpls.c
index 6eb9f66affc8..f62a6fb6d53e 100644
--- a/sys/net/if_mpls.c
+++ b/sys/net/if_mpls.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: if_mpls.c,v 1.9 2013/07/15 12:10:34 kefren Exp $ */
+/*	$NetBSD: if_mpls.c,v 1.10 2013/07/23 11:11:55 kefren Exp $ */
 
 /*
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_mpls.c,v 1.9 2013/07/15 12:10:34 kefren Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_mpls.c,v 1.10 2013/07/23 11:11:55 kefren Exp $");
 
 #include "opt_inet.h"
 #include "opt_mpls.h"
@@ -95,7 +95,8 @@ static struct mbuf *mpls_label_inet6(struct mbuf *, union mpls_shim *, uint);
 static struct mbuf *mpls_prepend_shim(struct mbuf *, union mpls_shim *);
 
 extern int mpls_defttl, mpls_mapttl_inet, mpls_mapttl_inet6, mpls_icmp_respond,
-	mpls_forwarding, mpls_accept, mpls_mapprec_inet, mpls_mapclass_inet6;
+	mpls_forwarding, mpls_accept, mpls_mapprec_inet, mpls_mapclass_inet6,
+	mpls_rfc4182;
 
 /* ARGSUSED */
 void
@@ -325,6 +326,19 @@ mpls_lse(struct mbuf *m)
 	if ((m = mpls_ttl_dec(m)) == NULL)
 		goto done;
 
+	/* RFC 4182 */
+	if (mpls_rfc4182 != 0)
+		while((dst.smpls_addr.shim.label == MPLS_LABEL_IPV4NULL ||
+		    dst.smpls_addr.shim.label == MPLS_LABEL_IPV6NULL) &&
+		    __predict_false(dst.smpls_addr.shim.bos == 0)) {
+			m_adj(m, sizeof(union mpls_shim));
+			if (m->m_len < sizeof(union mpls_shim) &&
+			    (m = m_pullup(m, sizeof(union mpls_shim))) == NULL)
+				goto done;
+			dst.smpls_addr.s_addr =
+			    ntohl(mtod(m, union mpls_shim *)->s_addr);
+		}
+
 	if (dst.smpls_addr.shim.label <= MPLS_LABEL_RESMAX) {
 		/* Don't swap reserved labels */
 		switch (dst.smpls_addr.shim.label) {
diff --git a/sys/netmpls/mpls_proto.c b/sys/netmpls/mpls_proto.c
index 2c316d9accc3..609ba324b39c 100644
--- a/sys/netmpls/mpls_proto.c
+++ b/sys/netmpls/mpls_proto.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: mpls_proto.c,v 1.4 2013/07/18 06:23:07 kefren Exp $ */
+/*	$NetBSD: mpls_proto.c,v 1.5 2013/07/23 11:11:55 kefren Exp $ */
 
 /*
  * Copyright (c) 2010 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: mpls_proto.c,v 1.4 2013/07/18 06:23:07 kefren Exp $");
+__KERNEL_RCSID(0, "$NetBSD: mpls_proto.c,v 1.5 2013/07/23 11:11:55 kefren Exp $");
 
 #include "opt_inet.h"
 #include "opt_mbuftrace.h"
@@ -65,6 +65,7 @@ int mpls_forwarding = 0;
 int mpls_accept = 0;
 int mpls_mapprec_inet = 1;
 int mpls_mapclass_inet6 = 1;
+int mpls_rfc4182 = 1;
 
 void mpls_init(void)
 {
@@ -176,6 +177,12 @@ sysctl_net_mpls_setup(struct sysctllog **clog)
 		       SYSCTL_DESCR("MPLS queue length"),
 		       NULL, 0, &mplsintrq.ifq_maxlen, 0,
 		       CTL_NET, PF_MPLS, CTL_CREATE, CTL_EOL);
+	sysctl_createv(clog, 0, NULL, NULL,
+		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
+		       CTLTYPE_INT, "rfc4182",
+		       SYSCTL_DESCR("RFC 4182 conformance"),
+		       NULL, 0, &mpls_rfc4182, 0,
+		       CTL_NET, PF_MPLS, CTL_CREATE, CTL_EOL);
 #ifdef INET
 	sysctl_createv(clog, 0, NULL, NULL,
 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,