diff --git a/lib/server/ponse.js b/lib/server/ponse.js
index bdb6b340..a5283d00 100644
--- a/lib/server/ponse.js
+++ b/lib/server/ponse.js
@@ -134,7 +134,7 @@
                     'Content-Length':   p.range.size
                 });
             
-            cmp             = Util.strCmp(ext, '.appcache');
+            cmp             = Util.strCmp(extension, '.appcache');
             if (!p.cache || cmp)
                 maxAge  = 0;