Adding information on internal reverse proxy

For more information see: http://stackoverflow.com/questions/9029757/how-do-i-get-the-user-ip-address-in-symfony2-controller

Author: tcz

components/http_foundation/trusting_proxies.rst

@@ -24,6 +24,12 @@ your proxy.
 
     // only trust proxy headers coming from this IP addresses
     Request::setTrustedProxies(array('192.0.0.1', '10.0.0.0/8'));
+    
+.. note::
+
+   When using Symfony's internal reverse proxy (``AppCache.php``) make sure to add 
+   ``127.0.0.1`` to the list of trusted proxies.
+
 
 Configuring Header Names
 ------------------------