Index: Makefile
diff -u Makefile.orig Makefile
--- Makefile.orig	2013-06-02 23:07:08.000000000 +0900
+++ Makefile	2013-10-05 01:00:09.143956067 +0900
@@ -94,11 +94,11 @@
 
 realinstall:
 	${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m 555 dtcps \
-		${BINDIR}/dtcps
+		${DESTDIR}${BINDIR}/dtcps
 	${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m 555 dtcpc \
-		${BINDIR}/dtcpc
+		${DESTDIR}${BINDIR}/dtcpc
 	${INSTALL} ${COPY} -o ${BINOWN} -g ${BINGRP} -m 555 dtcpauth \
-		${BINDIR}/dtcpauth
+		${DESTDIR}${BINDIR}/dtcpauth
 
 dist:
 	@data=`date +%Y%m%d`; \