diff --git a/configure.ac b/configure.ac
index 9d0df964..21a6b444 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,7 +1,7 @@
 #                                               -*- Autoconf -*-
 # Process this file with autoconf to produce a configure script.
 
-AC_PREREQ([2.67])
+AC_PREREQ([2.69])
 
 AC_INIT(
     [crosstool-NG],
@@ -93,7 +93,7 @@ AC_PROG_CC
 AM_PROG_CC_C_O
 AC_PROG_CXX
 AC_PROG_CPP
-AC_PROG_LEX
+AC_PROG_LEX([yywrap])
 AC_PROG_YACC
 AS_IF([test -z "$CC" -o -z "$CXX"],
       [AC_MSG_ERROR([no suitable compiler found])])
@@ -300,7 +300,6 @@ CTNG_SET_KCONFIG_OPTION([sha512sum])
 
 # FIXME why checking if not using the result? We don't provide replacemant malloc/alloca/...
 AC_C_INLINE
-AC_HEADER_STDC
 AC_FUNC_MALLOC
 AC_FUNC_REALLOC
 AC_FUNC_ALLOCA