diff -ruN yc.el.orig/Makefile yc.el/Makefile
--- yc.el.orig/Makefile	2009-12-25 11:36:54.000000000 +0900
+++ yc.el/Makefile	2009-12-25 11:40:36.000000000 +0900
@@ -30,6 +30,10 @@
 
 .include <bsd.port.pre.mk>
 
+.if $(EMACS_MAJOR_VER) >= 23
+BROKEN=		Does not support emacs23.x or later
+.endif
+
 .if defined(WITH_ICANNA)
 RUN_DEPENDS+=	${LOCALBASE}/bin/icanna:${PORTSDIR}/japanese/icanna
 .endif