--- configure.in
+++ configure.in
@@ -509,9 +509,6 @@
 fi
 
 
-# checks for UNIX variants that set C preprocessor variables
-AC_AIX
-
 # Check for unsupported systems
 case $ac_sys_system/$ac_sys_release in
 atheos*|Linux*/1*)
@@ -572,6 +569,9 @@
     ;;
 esac
 
+# checks for UNIX variants that set C preprocessor variables
+AC_AIX
+
 AC_SUBST(ARCH)
 AC_MSG_CHECKING(ARCH)
 ARCH=`uname -m`
@@ -3406,9 +3406,18 @@
 fi
 
 # check for readline 4.0
-AC_CHECK_LIB(readline, rl_pre_input_hook,
-	AC_DEFINE(HAVE_RL_PRE_INPUT_HOOK, 1,
-        [Define if you have readline 4.0]), ,$READLINE_LIBS)
+AC_MSG_CHECKING([for rl_pre_input_hook in -lreadline])
+AC_CACHE_VAL(ac_cv_have_rl_re_input_hook, [
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([#include <stdio.h>
+#include <readline/readline.h>],
+				   [return rl_pre_input_hook != 0])],
+		  ac_cv_have_rl_re_input_hook=yes,
+		  ac_cv_have_rl_re_input_hook=no)])
+AC_MSG_RESULT($ac_cv_have_rl_re_input_hook)
+if test "$ac_cv_have_rl_re_input_hook" = yes; then
+  AC_DEFINE(HAVE_RL_PRE_INPUT_HOOK, 1,
+            [Define if you have readline 4.0])
+fi
 
 # also in 4.0
 AC_CHECK_LIB(readline, rl_completion_display_matches_hook,