diff --git a/acconfig.h b/acconfig.h
index ab0cc886ec1eb46a753b3bbe02db02385a56ed7d..acf11d59a620982f7d0d14bd7d9eb74eb29de19c 100644
--- a/acconfig.h
+++ b/acconfig.h
@@ -54,3 +54,11 @@
 
 /* Define if you have a working OpenSSL installation */
 #undef OPENSSL_ENABLED
+
+/* Define the one correct non-blocking socket method below */
+#undef HAVE_FIONBIO
+#undef HAVE_IOCTLSOCKET
+#undef HAVE_IOCTLSOCKET_CASE
+#undef HAVE_O_NONBLOCK
+#undef HAVE_DISABLED_NONBLOCKING
+