diff --git a/Makefile.am b/Makefile.am
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,7 @@
 ACLOCAL_AMFLAGS = -I m4
 
+AM_CXXFLAGS = $(WARNINGCXXFLAGS)
+
 AM_CPPFLAGS = -I$(top_srcdir) -I$(top_builddir)
 LDADD = $(top_builddir)/lemon/libemon.la
 
@@ -9,8 +11,12 @@
 	m4/lx_check_cplex.m4 \
 	m4/lx_check_glpk.m4 \
 	m4/lx_check_soplex.m4 \
+	m4/lx_check_coin.m4 \
 	CMakeLists.txt \
 	cmake/FindGhostscript.cmake \
+	cmake/FindCPLEX.cmake \
+	cmake/FindGLPK.cmake \
+	cmake/FindCOIN.cmake \
 	cmake/version.cmake.in \
 	cmake/version.cmake \
 	cmake/nsis/lemon.ico \
@@ -36,9 +42,13 @@
 include lemon/Makefile.am
 include test/Makefile.am
 include doc/Makefile.am
-include demo/Makefile.am
 include tools/Makefile.am
 
+DIST_SUBDIRS = demo
+
+demo:
+	$(MAKE) $(AM_MAKEFLAGS) -C demo
+
 MRPROPERFILES = \
 	aclocal.m4 \
 	config.h.in \
@@ -65,4 +75,4 @@
 	zcat $(PACKAGE)-$(VERSION).tar.gz | \
 	bzip2 --best -c > $(PACKAGE)-$(VERSION).tar.bz2
 
-.PHONY: mrproper dist-bz2 distcheck-bz2
+.PHONY: demo mrproper dist-bz2 distcheck-bz2