Index: includes/common.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/common.inc,v
retrieving revision 1.1038
diff -u -r1.1038 common.inc
--- includes/common.inc	2 Nov 2009 03:46:43 -0000	1.1038
+++ includes/common.inc	2 Nov 2009 22:16:50 -0000
@@ -2457,7 +2457,13 @@
   }
 
   global $base_url, $base_secure_url, $base_insecure_url;
-  $script = &drupal_static(__FUNCTION__);
+  // Use a static variable to store a reference to drupal_static()'s data so
+  // drupal_static() only needs to be called once.
+  static $drupal_static = array();
+  if (!isset($drupal_static[__FUNCTION__])) {
+    $drupal_static[__FUNCTION__] = &drupal_static(__FUNCTION__);
+  }
+  $script = &$drupal_static[__FUNCTION__];
 
   if (!isset($script)) {
     // On some web servers, such as IIS, we can't omit "index.php". So, we
Index: includes/bootstrap.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/bootstrap.inc,v
retrieving revision 1.320
diff -u -r1.320 bootstrap.inc
--- includes/bootstrap.inc	2 Nov 2009 03:46:43 -0000	1.320
+++ includes/bootstrap.inc	2 Nov 2009 22:16:47 -0000
@@ -2032,9 +2032,13 @@
   // Reset a single value, or all values.
   if ($reset) {
     if (isset($name)) {
-      unset($data[$name]);
+      $data[$name] = NULL; // Set data to NULL
+      unset($data[$name]); // Remove reference
     }
     else {
+      foreach (array_keys($data) as $name) {
+        $data[$name] = NULL; // Set data to NULL
+      }
       $data = array();
     }
     // We must return a reference to a variable.
Index: includes/path.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/path.inc,v
retrieving revision 1.47
diff -u -r1.47 path.inc
--- includes/path.inc	24 Oct 2009 05:13:43 -0000	1.47
+++ includes/path.inc	2 Nov 2009 22:16:50 -0000
@@ -45,14 +45,20 @@
  */
 function drupal_lookup_path($action, $path = '', $path_language = '') {
   global $language;
-  $cache = &drupal_static(__FUNCTION__, array(
-    'map' => array(),
-    'no_source' => array(),
-    'whitelist' => NULL,
-    'system_paths' => array(),
-    'no_aliases' => array(),
-    'first_call' => TRUE,
-  ));
+  // Use a static variable to store a reference to drupal_static()'s data so
+  // drupal_static() only needs to be called once.
+  static $drupal_static = array();
+  if (!isset($drupal_static[__FUNCTION__])) {
+    $drupal_static[__FUNCTION__] = &drupal_static(__FUNCTION__, array(
+      'map' => array(),
+      'no_source' => array(),
+      'whitelist' => NULL,
+      'system_paths' => array(),
+      'no_aliases' => array(),
+      'first_call' => TRUE,
+    ));
+  }
+  $cache = &$drupal_static[__FUNCTION__];
 
   // Retrieve the path alias whitelist.
   if (!isset($cache['whitelist'])) {
@@ -245,7 +251,13 @@
  *   not found.
  */
 function arg($index = NULL, $path = NULL) {
-  $arguments = &drupal_static(__FUNCTION__);
+  // Use a static variable to store a reference to drupal_static()'s data so
+  // drupal_static() only needs to be called once.
+  static $drupal_static = array();
+  if (!isset($drupal_static[__FUNCTION__])) {
+    $drupal_static[__FUNCTION__] = &drupal_static(__FUNCTION__);
+  }
+  $arguments = &$drupal_static[__FUNCTION__];
 
   if (!isset($path)) {
     $path = $_GET['q'];
Index: includes/module.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/module.inc,v
retrieving revision 1.164
diff -u -r1.164 module.inc
--- includes/module.inc	1 Nov 2009 22:10:07 -0000	1.164
+++ includes/module.inc	2 Nov 2009 22:16:50 -0000
@@ -367,7 +367,13 @@
  * @see module_implements_write_cache().
  */
 function module_implements($hook, $sort = FALSE, $reset = FALSE) {
-  $implementations = &drupal_static(__FUNCTION__, array());
+  // Use a static variable to store a reference to drupal_static()'s data so
+  // drupal_static() only needs to be called once.
+  static $drupal_static = array();
+  if (!isset($drupal_static[__FUNCTION__])) {
+    $drupal_static[__FUNCTION__] = &drupal_static(__FUNCTION__, array());
+  }
+  $implementations = &$drupal_static[__FUNCTION__];
 
   // We maintain a persistent cache of hook implementations in addition to the
   // static cache to avoid looping through every module and every hook on each