diff --git a/Makefile.am b/Makefile.am
index b374969..c93c261 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -27,6 +27,7 @@ AUTOMAKE_OPTIONS	= foreign
 SUBDIRS			= doc src contrib
 dist_noinst_SCRIPTS	= autogen.sh
 EXTRA_DIST		= ChangeLog COPYING README INSTALL doxy.cfg .gitignore
+ACLOCAL_AMFLAGS		= -I m4
 
 CLEANFILES		= cscope.in.out cscope.out cscope.po.out *~
 DISTCLEANFILES		= Makefile.in ChangeLog