Index: wp-comments-post.php
===================================================================
--- wp-comments-post.php	(revision 4887)
+++ wp-comments-post.php	(working copy)
@@ -1,4 +1,10 @@
 <?php
+if ($_SERVER["REQUEST_METHOD"] != "POST") {
+    header('Allow: POST');
+	header("HTTP/1.1 405 Method Not Allowed");
+	header("Content-type: text/plain");
+    exit;
+}
 require( dirname(__FILE__) . '/wp-config.php' );
 
 nocache_headers();