diff --git a/configure.ac b/configure.ac
index 3b40dc2..9503fc1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([libsharp2], [1.0.0])
+AC_INIT([libsharp2],[1.0.0])
 AM_INIT_AUTOMAKE([foreign subdir-objects -Wall -Werror])
 AM_MAINTAINER_MODE([enable])
 
@@ -20,13 +20,13 @@ dnl
 m4_ifdef([AM_SILENT_RULES], [AM_SILENT_RULES([yes])])
 
 
-AC_PROG_CC_C99
+m4_version_prereq(2.70, [AC_PROG_CC], [AC_PROG_CC_C99])
 AC_OPENMP
 
 # add math library
 LIBS="-lm"
 
-AC_PROG_LIBTOOL
+LT_INIT
 
 tmpval=`echo $CFLAGS | grep -c '\-DMULTIARCH'`
 AM_CONDITIONAL([HAVE_MULTIARCH], [test $tmpval -gt 0])