Support DESTDIR and do not specify the user or group when installing.
--- Makefile.in.orig	2005-05-20 15:10:24.000000000 -0400
+++ Makefile.in	2014-10-01 17:05:59.000000000 -0400
@@ -103,6 +103,7 @@
 		CGIBINDIR=$(CGIBINDIR) \
 		MANDIR=$(MANDIR) \
 		WEBGROUP=$(WEBGROUP) \
+		DESTDIR=$(DESTDIR) \
 	) ; done
 
 
@@ -110,11 +111,11 @@
 
 installthis:
 	-mkdir -p $(DESTDIR)$(BINDIR)
-	$(INSTALL) -m 555 -o bin -g bin thttpd $(DESTDIR)$(BINDIR)
+	$(INSTALL) -m 555 thttpd $(DESTDIR)$(BINDIR)
 
 install-man:
 	-mkdir -p $(DESTDIR)$(MANDIR)/man8
-	$(INSTALL) -m 444 -o bin -g bin thttpd.8 $(DESTDIR)$(MANDIR)/man8
+	$(INSTALL) -m 444 thttpd.8 $(DESTDIR)$(MANDIR)/man8
 
 installsubdirs:
 	for i in $(SUBDIRS) ; do ( \
@@ -125,6 +126,7 @@
 		CGIBINDIR=$(CGIBINDIR) \
 		MANDIR=$(MANDIR) \
 		WEBGROUP=$(WEBGROUP) \
+		DESTDIR=$(DESTDIR) \
 		install \
 	) ; done