--- modules/memcache/memcache.inc	2009-07-02 00:09:45.000000000 -0400
+++ modules/memcache/memcache.inc	2009-07-02 00:15:17.000000000 -0400
@@ -118,3 +118,100 @@ function cache_clear_all($cid = NULL, $t
 function memcache_clone($object) {
   return version_compare(phpversion(), '5.0') < 0 ? $object : clone($object);
 }
+
+/**
+ *
+ * Allows memcache & authcache dual functionality under the memcache module.
+ *
+ */
+
+function page_cache_fastpath() {
+  global $base_root, $cache, $conf;
+
+  // User is logged in but their role should not receive any cached pages
+  // (i.e., cached anonymous pages, since they have no authcache key)
+  if(isset($_COOKIE['drupal_user']) && !isset($_COOKIE['authcache'])) {
+    return FALSE;
+  }
+
+  if (empty($_POST) && !isset($_COOKIE['nocache'])) {
+
+    // Connect to database if 'db' engine selected
+    if($conf['cacherouter']['default']['engine'] == 'db') {
+      require_once './includes/database.inc';
+      db_set_active();
+    }
+
+    if (!isset($cache)) {
+      $key = (isset($_COOKIE['authcache']) && $_COOKIE['authcache']) ? $_COOKIE['authcache'] : '';
+      $page = cache_get($key . $base_root . request_uri(), 'cache_page');
+      if (!empty($page)) {
+
+        // Set HTTP headers in preparation for a cached page response.
+
+        // The following headers force validation of cache:
+        header("Expires: Sun, 19 Nov 1978 05:00:00 GMT");
+        header("Cache-Control: must-revalidate");
+
+        // Visitors can keep a local cache of the page, but must revalidate
+        // it on every request.  Then, they are given a '304 Not Modified'
+        // response with no body as long as they say page has not been modified.
+        $last_modified = gmdate('D, d M Y H:i:s', $page->created) .' GMT';
+
+        // See if the client has provided the required HTTP caching header
+        // (No need for ETag; resolution of HTTP date value is sufficient)
+        $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? stripslashes($_SERVER['HTTP_IF_MODIFIED_SINCE']) : FALSE;
+
+        if ($if_modified_since == $last_modified) {
+
+          // Save cache benchmark
+          if(isset($_COOKIE['authcache_debug'])) {
+            setcookie('cache_render',timer_read('page'));
+          }
+
+          header('HTTP/1.1 304 Not Modified');
+          return TRUE;
+        }
+
+        // Time from when page was saved to cache
+        header("Last-Modified: $last_modified");
+
+        // Send the original request's headers.
+        $headers = explode("\n", $page->headers);
+        foreach ($headers as $header) {
+          header($header);
+        }
+
+        // Checking if first chars are compressed (always the same pattern for every header)
+        if (substr($page->data, 0,3) == "\x1f\x8b\x08") {
+
+          // Determine if the browser accepts gzipped data.
+          if (@strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') === FALSE && function_exists('gzencode')) {
+            // Strip the gzip header and run uncompress.
+            $page->data = gzinflate(substr(substr($page->data, 10), 0, -8));
+          }
+          elseif (function_exists('gzencode')) {
+            // Send gzip header to the browser
+            header('Content-Encoding: gzip');
+          }
+        }
+
+        // Save cache benchmark
+        if(isset($_COOKIE['authcache_debug'])) {
+          setcookie('cache_render',timer_read('page'));
+        }
+
+        print $page->data;
+        return TRUE;
+      }
+    }
+  }
+
+  // Cache was temporarily disabled (most likely from drupal_set_message()/drupal_goto() redirect)
+  if(isset($_COOKIE['nocache_temp'])) {
+    setcookie('nocache', '', time() - 36000, ini_get('session.cookie_path'), ini_get('session.cookie_domain'), ini_get('session.cookie_secure') == '1');
+    setcookie('nocache_temp', '', time() - 36000, ini_get('session.cookie_path'), ini_get('session.cookie_domain'), ini_get('session.cookie_secure') == '1');
+  }
+
+  return FALSE;
+}