diff --git a/net-mgmt/trafd/Makefile b/net-mgmt/trafd/Makefile
index aef90abed843..a6c98ec8ca20 100644
--- a/net-mgmt/trafd/Makefile
+++ b/net-mgmt/trafd/Makefile
@@ -37,4 +37,11 @@ do-install:
 	@${INSTALL_DATA} ${WRKSRC}/README ${DOCSDIR}
 .endif
 
-.include <bsd.port.mk>
+.include <bsd.port.pre.mk>
+post-patch:
+.if	${OSVERSION} >= 800000
+	@${REINPLACE_CMD} -e "s|-DCSLIP|-UCSLIP|" \
+	    ${WRKSRC}/Makefile.inc
+.endif
+
+.include <bsd.port.post.mk>
diff --git a/net-mgmt/trafd/files/patch-Makefile.inc b/net-mgmt/trafd/files/patch-Makefile.inc
index c5e73a0dc114..f34d748eaf9c 100644
--- a/net-mgmt/trafd/files/patch-Makefile.inc
+++ b/net-mgmt/trafd/files/patch-Makefile.inc
@@ -1,5 +1,5 @@
---- Makefile.inc.orig	2009-04-21 09:52:03.000000000 +0100
-+++ Makefile.inc	2009-04-21 09:54:50.000000000 +0100
+--- Makefile.inc.orig	2002-11-27 08:40:39.000000000 -0500
++++ Makefile.inc	2009-05-29 14:09:06.000000000 -0400
 @@ -18,11 +18,11 @@
  
  PREFIX?=/usr/local
@@ -15,3 +15,12 @@
  TRAFSTAT_PORT=150
  
  TRAFLOG_FMT=${PREFIX}/etc/traflog.format
+@@ -40,6 +40,7 @@
+ 	-DPATH_TRAFSTAT=\"${TRAFSTAT}\" \
+ 	-DPATH_TRAFSTAT_LOG=\"${TRAFSTAT_LOG}\" \
+ 	-DPATH_TRAFLOG_FMT=\"${TRAFLOG_FMT}\" \
+-	-DTRAFSTAT_PORT=${TRAFSTAT_PORT}
++	-DTRAFSTAT_PORT=${TRAFSTAT_PORT} \
++	-DCSLIP
+ 
+ 
diff --git a/net-mgmt/trafd/files/patch-lib_interfaces.c b/net-mgmt/trafd/files/patch-lib_interfaces.c
new file mode 100644
index 000000000000..c1d710d24eab
--- /dev/null
+++ b/net-mgmt/trafd/files/patch-lib_interfaces.c
@@ -0,0 +1,37 @@
+--- lib/interfaces.c.orig	2002-11-27 08:40:33.000000000 -0500
++++ lib/interfaces.c	2009-05-29 14:20:33.000000000 -0400
+@@ -32,7 +32,9 @@
+ #include <netinet/in.h>
+ #include <net/ethernet.h>
+ #include <net/ppp_defs.h>
++#ifdef CSLIP
+ #include <net/slip.h>
++#endif
+ #include <netinet/if_ether.h>
+ #include <netinet/in_systm.h>
+ #include <netinet/ip.h>
+@@ -60,8 +62,10 @@
+ 
+ static struct printer printers[] = {
+ 		{ ether_if_print,       DLT_EN10MB },
++#ifdef CSLIP
+ 		{ sl_if_print,          DLT_SLIP },
+ 		{ sl_bsdos_if_print,    DLT_SLIP_BSDOS },
++#endif
+ 		{ ppp_if_print,         DLT_PPP },
+ 		{ ppp_bsdos_if_print,   DLT_PPP_BSDOS },
+ 		{ null_if_print,        DLT_NULL },
+@@ -232,6 +236,8 @@
+ 	processing_ip(p, length);
+ }
+ 
++#ifdef CSLIP
++
+ /* XXX BSD/OS 2.1 compatibility */
+ #if !defined(SLIP_HDRLEN) && defined(SLC_BPFHDR)
+ #define SLIP_HDRLEN SLC_BPFHDR
+@@ -288,3 +294,4 @@
+ 	processing_ip(p + SLIP_HDRLEN, length);
+ 
+ }
++#endif