diff --git a/configure.ac b/configure.ac
index 436429e..74946b0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -5,14 +5,14 @@ AC_PREREQ(2.68)
 
 AC_CONFIG_SRCDIR([src/apple2.cpp])
 
-AM_CONFIG_HEADER(config.h)
+AC_CONFIG_HEADERS([config.h])
 AM_INIT_AUTOMAKE
 
 
 
 # Checks for programs.
 AC_PROG_CXX
-AC_LANG_CPLUSPLUS
+AC_LANG([C++])
 AC_PROG_CPP
 AC_PROG_INSTALL
 AC_PROG_LN_S