--- /dev/null
+<?php
+error_reporting(0);
+
+$ts = $_REQUEST['ts'];
+
+$ifModifiedSince = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']) : false;
+if ($ifModifiedSince == $ts) {
+ header('HTTP/1.0 304 Not Modified');
+ die; // stop processing
+}
+
+header("Last-Modified: " . $ts);
+echo "OK: " . $ts;
+
+?>