Index: django/utils/cache.py
===================================================================
--- django/utils/cache.py	(revision 17929)
+++ django/utils/cache.py	(working copy)
@@ -234,8 +234,11 @@
     if cache is None:
         cache = get_cache(settings.CACHE_MIDDLEWARE_ALIAS)
     if response.has_header('Vary'):
-        headerlist = ['HTTP_'+header.upper().replace('-', '_')
-                      for header in cc_delim_re.split(response['Vary'])]
+        headerlist = []
+        for header in cc_delim_re.split(response['Vary']):
+            header = header.upper().replace('-', '_')
+            if header != 'ACCEPT_LANGUAGE':
+                headerlist.append('HTTP_' + header)
         cache.set(cache_key, headerlist, cache_timeout)
         return _generate_cache_key(request, request.method, headerlist, key_prefix)
     else: