diff --git a/configure.ac b/configure.ac
index 948abf3..a86a648 100644
--- a/configure.ac
+++ b/configure.ac
@@ -3,7 +3,7 @@
 
 AC_PREREQ([2.68])
 AC_INIT([pixz], [1.0.2], [https://github.com/vasi/pixz/issues])
-AC_CONFIG_MACRO_DIRS([m4])
+AC_CONFIG_MACRO_DIR([m4])
 AC_CONFIG_SRCDIR([src/pixz.c])
 AC_CONFIG_HEADERS([config.h])