diff --git a/configure.in b/configure.in
index 9aad095..880195c 100644
--- a/configure.in
+++ b/configure.in
@@ -1,4 +1,7 @@
-dnl Process this file with autoconf 2.0 or later to make a configure script.
+dnl ***********************************************
+dnl * Please run autoreconf to test your changes! *
+dnl ***********************************************
+dnl NOTE: autoconf 2.64 doesn't seem to work (use 1.63).
 
 # Set VERSION so we only need to edit in one place (i.e., here)
 m4_define(PYTHON_VERSION, 2.6)