diff --git a/lang/cmucl/Makefile b/lang/cmucl/Makefile
index fa74a8e1917f..b779da8ab177 100644
--- a/lang/cmucl/Makefile
+++ b/lang/cmucl/Makefile
@@ -1,34 +1,40 @@
 # New ports collection makefile for:    CMUCL
 # Date created:         Jul, 15, 1997
 # Whom:                 cracauer@cons.org "Martin Cracauer"
 #
 # $FreeBSD$
 #
 #
 
 PORTNAME=	cmucl
 PORTVERSION=	18d
 CATEGORIES=	lang
 MASTER_SITES=	http://www2.cons.org/freebsd-distfiles/ \
 		${MASTER_SITE_LOCAL}
 MASTER_SITE_SUBDIR=	cracauer
 DISTNAME=	cmucl-18d-x86-FreeBSD
 
 MAINTAINER=	cracauer@cons.org
 
 USE_BZIP2=	YES
 NO_WRKSUBDIR=	yes
 NO_BUILD=	yes
 MAN1=		lisp.1 cmucl.1
 
+.include <bsd.port.pre.mk>
+
+.if ${OSVERSION} >= 500000
+LIB_DEPENDS+=	c.4:${PORTSDIR}/misc/compat4x
+.endif
+
 do-install:
 	${INSTALL} -c -o ${BINOWN} -g ${BINGRP} ${WRKDIR}/bin/lisp ${PREFIX}/bin
 	(cd ${WRKDIR} && tar fc - lib ) | (cd ${PREFIX} && tar fx -)
 	-${MKDIR} ${PREFIX}/share/doc/cmucl
 	(cd ${WRKDIR} && tar fc - doc) | (cd ${PREFIX}/share && tar fx -)
 	${INSTALL} -c -o ${BINOWN} -g ${BINGRP} ${WRKDIR}/man/man1/cmucl.1 \
 		${PREFIX}/man/man1
 	${INSTALL} -c -o ${BINOWN} -g ${BINGRP} ${WRKDIR}/man/man1/lisp.1 \
 		${PREFIX}/man/man1
 
-.include <bsd.port.mk>
+.include <bsd.port.post.mk>