Add note to main install guide

Jamie Hannaford · Jamie Hannaford · commit 1e007ac9fad7 · 2015-04-29T11:03:06.000+02:00
diff --git a/doc/index.rst b/doc/index.rst
@@ -30,6 +30,10 @@ Read the :doc:`getting-started-with-openstack` or
 :doc:`getting-started-with-rackspace` to help you get started with basic
 Compute operations.
 
+.. note::
+
+  If you are running PHP 5.3, please see our :doc:`using-php-5.3` guide.
+
 Services
 --------
 
