diff -Naur a/Makedefs.in b/Makedefs.in
--- a/Makedefs.in	2005-10-28 22:32:59.000000000 +0200
+++ b/Makedefs.in	2009-03-23 23:40:35.928865178 +0100
@@ -46,6 +46,7 @@
 #
 # Directories...
 #
+DESTDIR = @DESTDIR@
 
 bindir		=	@bindir@
 datadir		=	@datadir@
diff -Naur a/data/Makefile b/data/Makefile
--- a/data/Makefile	2004-05-10 03:14:53.000000000 +0200
+++ b/data/Makefile	2009-03-23 23:35:27.850856359 +0100
@@ -53,11 +53,11 @@
 #
 
 install:
-	if [ ! -d $(datadir)/htmldoc/data ]; then\
-		$(MKDIR) $(datadir)/htmldoc/data;\
+	if [ ! -d $(DESTDIR)$(datadir)/htmldoc/data ]; then\
+		$(MKDIR) $(DESTDIR)$(datadir)/htmldoc/data;\
 	fi
-	$(CP) $(FILES) $(datadir)/htmldoc/data
-	$(CHMOD) ugo+r $(datadir)/htmldoc/data/*
+	$(CP) $(FILES) $(DESTDIR)$(datadir)/htmldoc/data
+	$(CHMOD) ugo+r $(DESTDIR)$(datadir)/htmldoc/data/*
 
 
 #
diff -Naur a/doc/Makefile b/doc/Makefile
--- a/doc/Makefile	2005-10-28 22:32:59.000000000 +0200
+++ b/doc/Makefile	2009-03-23 23:38:19.478865122 +0100
@@ -42,7 +42,7 @@
 DOCUMENTS =	htmldoc.html htmldoc.pdf htmldoc.ps
 DOCFILES =	help.html htmldoc.pdf
 
-HTMLDOC	=	../htmldoc/htmldoc$(EXEEXT) --datadir .. --strict --verbose
+HTMLDOC	=	htmldoc$(EXEEXT) --datadir .. --strict --verbose
 
 
 #
@@ -57,16 +57,16 @@
 #
 
 install: $(DOCUMENTS)
-	if [ ! -d $(datadir)/doc/htmldoc ]; then\
-		$(MKDIR) $(datadir)/doc/htmldoc;\
+	if [ ! -d $(DESTDIR)$(datadir)/doc/htmldoc ]; then\
+		$(MKDIR) $(DESTDIR)$(datadir)/doc/htmldoc;\
 	fi
-	$(CP) $(DOCFILES) $(datadir)/doc/htmldoc
-	$(CHMOD) ugo+r $(datadir)/doc/htmldoc/*
-	if [ ! -d $(mandir)/man1 ]; then\
-		$(MKDIR) $(mandir)/man1;\
+	$(CP) $(DOCFILES) $(DESTDIR)$(datadir)/doc/htmldoc
+	$(CHMOD) ugo+r $(DESTDIR)$(datadir)/doc/htmldoc/*
+	if [ ! -d $(DESTDIR)$(mandir)/man1 ]; then\
+		$(MKDIR) $(DESTDIR)$(mandir)/man1;\
 	fi
-	$(CP) htmldoc.man $(mandir)/man1/htmldoc.1
-	$(CHMOD) ugo+r $(mandir)/man1/htmldoc.1
+	$(CP) htmldoc.man $(DESTDIR)$(mandir)/man1/htmldoc.1
+	$(CHMOD) ugo+r $(DESTDIR)$(mandir)/man1/htmldoc.1
 
 
 #
diff -Naur a/fonts/Makefile b/fonts/Makefile
--- a/fonts/Makefile	2005-10-28 22:32:59.000000000 +0200
+++ b/fonts/Makefile	2009-03-23 23:39:07.608863524 +0100
@@ -75,14 +75,14 @@
 
 install:
 	echo "Installing font files in $(datadir)/htmldoc/fonts..."
-	if [ ! -d $(datadir)/htmldoc/fonts ]; then\
-		$(MKDIR) $(datadir)/htmldoc/fonts;\
+	if [ ! -d $(DESTDIR)$(datadir)/htmldoc/fonts ]; then\
+		$(MKDIR) $(DESTDIR)$(datadir)/htmldoc/fonts;\
 	fi
 	for font in $(FONTS); do \
-		$(CP) $$font.afm $(datadir)/htmldoc/fonts; \
-		$(CP) $$font.pfa $(datadir)/htmldoc/fonts; \
+		$(CP) $$font.afm $(DESTDIR)$(datadir)/htmldoc/fonts; \
+		$(CP) $$font.pfa $(DESTDIR)$(datadir)/htmldoc/fonts; \
 	done
-	$(CHMOD) ugo+r $(datadir)/htmldoc/fonts/*
+	$(CHMOD) ugo+r $(DESTDIR)$(datadir)/htmldoc/fonts/*
 
 
 #
diff -Naur a/htmldoc/Makefile b/htmldoc/Makefile
--- a/htmldoc/Makefile	2005-10-28 22:32:59.000000000 +0200
+++ b/htmldoc/Makefile	2009-03-23 23:40:02.078914179 +0100
@@ -50,11 +50,11 @@
 #
 
 install:	all
-	if [ ! -d $(bindir) ]; then\
-		$(MKDIR) $(bindir);\
+	if [ ! -d $(DESTDIR)$(bindir) ]; then\
+		$(MKDIR) $(DESTDIR)$(bindir);\
 	fi
-	cp htmldoc$(EXEEXT) $(bindir)
-	chmod ugo+rx $(bindir)/htmldoc$(EXEEXT)
+	cp htmldoc$(EXEEXT) $(DESTDIR)$(bindir)
+	chmod ugo+rx $(DESTDIR)$(bindir)/htmldoc$(EXEEXT)
 
 
 #