--- a/Makefile.in
+++ b/Makefile.in
@@ -178,66 +178,66 @@ distclean : clean
 #	rm -f configure
 
 installdirs :
-	$(srcdir)/mkinstalldirs $(includedir) $(libdir) $(bindir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(includedir) $(DESTDIR)$(libdir) $(DESTDIR)$(bindir)
 
 installincs : $(HFLS)
-	$(srcdir)/mkinstalldirs $(includedir)
-	$(INSTALL_DATA) $(HFLS) $(includedir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(includedir)
+	$(INSTALL_DATA) $(HFLS) $(DESTDIR)$(includedir)
 
 installthsl : $(LIB_TH_SL)
-	$(srcdir)/mkinstalldirs $(shlibdir)
-	$(INSTALL) $(LIB_TH_SL) $(shlibdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(shlibdir)
+	$(INSTALL) $(LIB_TH_SL) $(DESTDIR)$(shlibdir)
 
 installth : $(INSTALL_THREADS)
-	$(srcdir)/mkinstalldirs $(libdir)
-	$(INSTALL) $(LIB_TH) $(libdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(libdir)
+	$(INSTALL) $(LIB_TH) $(DESTDIR)$(libdir)
 @CXX_OFF@	@echo "Enter 'make installthcxx' to install the threaded C++ library"
 @SL_OFF@	@echo "Enter 'make installthsl' to install the threaded shared-library"
 
 installthcxxsl : $(LIB_TH_CXX_SL)
-	$(srcdir)/mkinstalldirs $(shlibdir)
-	$(INSTALL) $(LIB_TH_CXX_SL) $(shlibdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(shlibdir)
+	$(INSTALL) $(LIB_TH_CXX_SL) $(DESTDIR)$(shlibdir)
 
 installthcxx : $(INSTALL_TH_CXX)
-	$(srcdir)/mkinstalldirs $(libdir)
-	$(INSTALL) $(LIB_TH_CXX) $(libdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(libdir)
+	$(INSTALL) $(LIB_TH_CXX) $(DESTDIR)$(libdir)
 @SL_OFF@	@echo "Enter 'make installthcxxsl' to install the threaded C++ shared-library"
 
 installcxxsl : $(LIB_CXX_SL)
-	$(srcdir)/mkinstalldirs $(shlibdir)
-	$(INSTALL) $(LIB_CXX_SL) $(shlibdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(shlibdir)
+	$(INSTALL) $(LIB_CXX_SL) $(DESTDIR)$(shlibdir)
 
 installcxx : $(INSTALL_CXX)
-	$(srcdir)/mkinstalldirs $(libdir)
-	$(INSTALL) $(LIB_CXX) $(libdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(libdir)
+	$(INSTALL) $(LIB_CXX) $(DESTDIR)$(libdir)
 @TH_OFF@	@echo "Enter 'make installthcxx' to install the threaded C++ library"
 @SL_OFF@	@echo "Enter 'make installcxxsl' to install the C++ shared-library"
 
 installsl : $(LIB_SL)
-	$(srcdir)/mkinstalldirs $(shlibdir)
-	$(INSTALL) $(LIB_SL) $(shlibdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(shlibdir)
+	$(INSTALL) $(LIB_SL) $(DESTDIR)$(shlibdir)
 @CXX_OFF@	@echo "Enter 'make installcxxsl' to install the C++ shared-library"
 @TH_OFF@	@echo "Enter 'make installthsl' to install thread shared-library"
 
 installlib : $(INSTALL_LIB)
-	$(srcdir)/mkinstalldirs $(libdir)
-	$(INSTALL) $(LIBRARY) $(libdir)
-	@RANLIB@ $(libdir)/$(LIBRARY)
-@SL_OFF@	@echo "Enter 'make installsl' to install $(LIB_SL) in $(shlibdir)"
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(libdir)
+	$(INSTALL) $(LIBRARY) $(DESTDIR)$(libdir)
+	@RANLIB@ $(DESTDIR)$(libdir)/$(LIBRARY)
+@SL_OFF@	@echo "Enter 'make installsl' to install $(LIB_SL) in $(DESTDIR)$(shlibdir)"
 @CXX_OFF@	@echo "Enter 'make installcxx' to install the C++ library"
 @TH_OFF@	@echo "Enter 'make installth' to install thread library"
 
 installdocs : $(srcdir)/docs/$(HTMLFILE) $(srcdir)/docs/$(TEXIFILE) \
 		$(srcdir)/docs/$(PDFFILE)
-	$(srcdir)/mkinstalldirs $(docdir)
-	$(INSTALL_DATA) $(srcdir)/docs/$(HTMLFILE) $(docdir)
-	$(INSTALL_DATA) $(srcdir)/docs/$(TEXIFILE) $(docdir)
-	$(INSTALL_DATA) $(srcdir)/docs/$(PDFFILE) $(docdir)
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(docdir)
+	$(INSTALL_DATA) $(srcdir)/docs/$(HTMLFILE) $(DESTDIR)$(docdir)
+	$(INSTALL_DATA) $(srcdir)/docs/$(TEXIFILE) $(DESTDIR)$(docdir)
+	$(INSTALL_DATA) $(srcdir)/docs/$(PDFFILE) $(DESTDIR)$(docdir)
 
 install : installincs installlib $(UTIL)
-	$(srcdir)/mkinstalldirs $(bindir)
-	$(INSTALL_PROGRAM) $(UTIL) $(bindir)
-	@echo "Enter 'make installdocs' to install $(DOCFILES) in $(docdir)"
+	$(srcdir)/mkinstalldirs $(DESTDIR)$(bindir)
+	$(INSTALL_PROGRAM) $(UTIL) $(DESTDIR)$(bindir)
+	@echo "Enter 'make installdocs' to install $(DOCFILES) in $(DESTDIR)$(docdir)"
 
 dmalloc.h.2 : $(srcdir)/configure
 	$(SHELL) $(srcdir)/configure