diff -up libircclient-1.7/src/Makefile.in.inst libircclient-1.7/src/Makefile.in
--- libircclient-1.7/src/Makefile.in.inst	2014-01-10 14:50:43.343991872 +0100
+++ libircclient-1.7/src/Makefile.in	2014-01-10 14:53:09.735435692 +0100
@@ -16,13 +16,13 @@ shared: libircclient.so
 shared_mingw: libircclient.dll
 
 install:
-	-mkdir -p $(DESTDIR)@prefix@/include
+	-mkdir -p $(DESTDIR)@includedir@
 	-mkdir -p $(DESTDIR)@libdir@
-	cp ../include/libircclient.h $(DESTDIR)@prefix@/include/libircclient.h
-	cp ../include/libirc_errors.h $(DESTDIR)@prefix@/include/libirc_errors.h
-	cp ../include/libirc_events.h  $(DESTDIR)@prefix@/include/libirc_events.h 
-	cp ../include/libirc_options.h  $(DESTDIR)@prefix@/include/libirc_options.h 
-	cp ../include/libirc_rfcnumeric.h  $(DESTDIR)@prefix@/include/libirc_rfcnumeric.h 
+	cp ../include/libircclient.h $(DESTDIR)@includedir@/libircclient.h
+	cp ../include/libirc_errors.h $(DESTDIR)@includedir@/libirc_errors.h
+	cp ../include/libirc_events.h  $(DESTDIR)@includedir@/libirc_events.h
+	cp ../include/libirc_options.h  $(DESTDIR)@includedir@/libirc_options.h
+	cp ../include/libirc_rfcnumeric.h  $(DESTDIR)@includedir@/libirc_rfcnumeric.h
 	cp libircclient.so $(DESTDIR)@libdir@/libircclient.so.$(APIVERSION)
 	ln -fs libircclient.so.$(APIVERSION) $(DESTDIR)@libdir@/libircclient.so