diff --git a/sysutils/throttle/Makefile b/sysutils/throttle/Makefile
index 0d93b9897d79..51fd3dafe8fb 100644
--- a/sysutils/throttle/Makefile
+++ b/sysutils/throttle/Makefile
@@ -17,4 +17,10 @@ GNU_CONFIGURE=	yes
 MAN1=		throttle.1
 PLIST_FILES=	bin/throttle
 
-.include <bsd.port.mk>
+.include <bsd.port.pre.mk>
+
+.if ${OSVERSION} < 500000
+BROKEN=		"Does not compile on 4.x"
+.endif
+
+.include <bsd.port.post.mk>