diff --git a/AUTHORS b/AUTHORS
index a34e558843..665a3a666b 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -234,6 +234,7 @@ answer newbie questions, and generally made Django that much better:
     Jay Parlar <parlar@gmail.com>
     pavithran s <pavithran.s@gmail.com>
     Barry Pederson <bp@barryp.org>
+    permonik@mesias.brnonet.cz
     petr.marhoun@gmail.com
     pgross@thoughtworks.com
     phaedo <http://phaedo.cx/>
diff --git a/django/utils/cache.py b/django/utils/cache.py
index 2494d7839e..9cf436d798 100644
--- a/django/utils/cache.py
+++ b/django/utils/cache.py
@@ -57,6 +57,13 @@ def patch_cache_control(response, **kwargs):
         cc = dict([dictitem(el) for el in cc])
     else:
         cc = {}
+
+    # If there's already a max-age header but we're being asked to set a new
+    # max-age, use the minumum of the two ages. In practice this happens when
+    # a decorator and a piece of middleware both operate on a given view.
+    if 'max-age' in cc and 'max_age' in kwargs:
+        kwargs['max_age'] = min(cc['max-age'], kwargs['max_age'])
+
     for (k,v) in kwargs.items():
         cc[k.replace('_', '-')] = v
     cc = ', '.join([dictvalue(el) for el in cc.items()])