Index: wp-includes/class-wp.php
===================================================================
--- wp-includes/class-wp.php	(revision 24501)
+++ wp-includes/class-wp.php	(working copy)
@@ -344,6 +344,11 @@
 						|| !empty($this->query_vars['pagename'])
 						|| !empty($this->query_vars['attachment'])
 						|| !empty($this->query_vars['attachment_id'])
+						|| ( !empty($this->query_vars['feed'])
+							&& in_array( $this->query_vars['feed'],
+								array( 'comments-rss', 'comments-rss2', 'comments-atom' )
+							)
+						)
 					)
 				)
 			)