diff --git a/wp-includes/feed-atom-comments.php b/wp-includes/feed-atom-comments.php
index a6f629ef8..545425c3d 100644
--- a/wp-includes/feed-atom-comments.php
+++ b/wp-includes/feed-atom-comments.php
@@ -12,7 +12,7 @@ echo '<?xml version="1.0" encoding="' . get_option('blog_charset') . '" ?' . '>'
 	xmlns="http://www.w3.org/2005/Atom"
 	xml:lang="<?php echo get_option('rss_language'); ?>"
 	xmlns:thr="http://purl.org/syndication/thread/1.0"
-	<?php do_action('atom_ns'); ?>
+	<?php do_action('atom_ns'); do_action('atom_comments_ns'); ?>
 >
 	<title type="text"><?php
 		if ( is_singular() )
diff --git a/wp-includes/feed-rss2-comments.php b/wp-includes/feed-rss2-comments.php
index 541dd0eac..e1d730a15 100644
--- a/wp-includes/feed-rss2-comments.php
+++ b/wp-includes/feed-rss2-comments.php
@@ -14,7 +14,7 @@ echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>';
 	xmlns:dc="http://purl.org/dc/elements/1.1/"
 	xmlns:atom="http://www.w3.org/2005/Atom"
 	xmlns:sy="http://purl.org/rss/1.0/modules/syndication/"
-	<?php do_action('rss2_comments_ns'); ?>
+	<?php do_action('rss2_ns'); do_action('rss2_comments_ns'); ?>
 	>
 <channel>
 	<title><?php