diff --git a/Makefile.am b/Makefile.am
--- a/Makefile.am
+++ b/Makefile.am
@@ -11,6 +11,8 @@
 	m4/lx_check_cplex.m4 \
 	m4/lx_check_glpk.m4 \
 	m4/lx_check_soplex.m4 \
+	m4/lx_check_clp.m4 \
+	m4/lx_check_cbc.m4 \
 	CMakeLists.txt \
 	cmake/FindGhostscript.cmake \
 	cmake/FindGLPK.cmake \