Index: includes/common.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/common.inc,v
retrieving revision 1.756.2.45
diff -u -p -r1.756.2.45 common.inc
--- includes/common.inc	16 Feb 2009 13:18:03 -0000	1.756.2.45
+++ includes/common.inc	19 Feb 2009 14:54:05 -0000
@@ -1568,7 +1568,8 @@ function l($text, $path, $options = arra
  * react to the closing of the page by calling hook_exit().
  */
 function drupal_page_footer() {
-  if (variable_get('cache', CACHE_DISABLED) != CACHE_DISABLED) {
+  global $no_cache;
+  if (variable_get('cache', CACHE_DISABLED) != CACHE_DISABLED && $no_cache != TRUE) {
     page_set_cache();
   }
 
Index: includes/language.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/language.inc,v
retrieving revision 1.14.2.1
diff -u -p -r1.14.2.1 language.inc
--- includes/language.inc	2 Jan 2009 23:37:48 -0000	1.14.2.1
+++ includes/language.inc	19 Feb 2009 14:54:06 -0000
@@ -10,7 +10,7 @@
  *  Choose a language for the page, based on language negotiation settings.
  */
 function language_initialize() {
-  global $user;
+  global $user, $no_cache;
 
   // Configured presentation language mode.
   $mode = variable_get('language_negotiation', LANGUAGE_NEGOTIATION_NONE);
@@ -59,6 +59,12 @@ function language_initialize() {
 
   // Browser accept-language parsing.
   if ($language = language_from_browser()) {
+
+    // If the language is set from  browser preferences, set $no_cache to TRUE
+    // to avoid caching the page in this language for subsequent requests.
+    if ($language != language_default()) {
+      $no_cache = TRUE;
+    }
     return $language;
   }