--- a/configure.ac
+++ b/configure.ac
@@ -7,7 +7,7 @@
 # (C) Copyright 2005-2007 Rémi Turboult <r3mi@users.sourceforge.net>
 #
 
-AC_PREREQ(2.60)
+AC_PREREQ([2.60])
 
 AC_INIT([libupnp], [1.6.21], [mroberto@users.sourceforge.net])
 dnl ############################################################################
@@ -549,10 +549,12 @@ AC_MSG_RESULT($docdir)
 #
 # Checks for programs
 #
-AC_PROG_CC
+AC_PROG_CC_STDC
+AC_USE_SYSTEM_EXTENSIONS
+AC_SYS_LARGEFILE
 AM_PROG_CC_C_O
 m4_ifdef([AM_PROG_AR], [AM_PROG_AR])
-AC_PROG_LIBTOOL
+LT_INIT
 AC_PROG_INSTALL
 AC_PROG_MAKE_SET
 AC_PROG_EGREP
@@ -592,8 +594,6 @@ echo "----------------------------------
 #
 AC_TYPE_SIZE_T
 AC_TYPE_OFF_T
-AC_DEFINE([_LARGE_FILE_SOURCE], [], [Large files support])
-AC_DEFINE([_FILE_OFFSET_BITS], [64], [File Offset size])
 
 
 #