Index: wp-includes/feed-rss2.php
===================================================================
--- wp-includes/feed-rss2.php	(revision 19067)
+++ wp-includes/feed-rss2.php	(working copy)
@@ -8,8 +8,9 @@
 header('Content-Type: ' . feed_content_type('rss-http') . '; charset=' . get_option('blog_charset'), true);
 $more = 1;
 
-echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>'; ?>
-
+echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>';
+do_action('rss2_pre');
+?>
 <rss version="2.0"
 	xmlns:content="http://purl.org/rss/1.0/modules/content/"
 	xmlns:wfw="http://wellformedweb.org/CommentAPI/"
Index: wp-includes/feed-atom.php
===================================================================
--- wp-includes/feed-atom.php	(revision 19067)
+++ wp-includes/feed-atom.php	(working copy)
@@ -8,7 +8,9 @@
 header('Content-Type: ' . feed_content_type('atom') . '; charset=' . get_option('blog_charset'), true);
 $more = 1;
 
-echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>'; ?>
+echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>';
+do_action('atom_pre');
+?>
 <feed
   xmlns="http://www.w3.org/2005/Atom"
   xmlns:thr="http://purl.org/syndication/thread/1.0"
Index: wp-includes/feed-rdf.php
===================================================================
--- wp-includes/feed-rdf.php	(revision 19067)
+++ wp-includes/feed-rdf.php	(working copy)
@@ -8,7 +8,9 @@
 header('Content-Type: ' . feed_content_type('rdf') . '; charset=' . get_option('blog_charset'), true);
 $more = 1;
 
-echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>'; ?>
+echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>';
+do_action('rdf_pre');
+?>
 <rdf:RDF
 	xmlns="http://purl.org/rss/1.0/"
 	xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
Index: wp-includes/feed-atom-comments.php
===================================================================
--- wp-includes/feed-atom-comments.php	(revision 19067)
+++ wp-includes/feed-atom-comments.php	(working copy)
@@ -7,6 +7,7 @@
 
 header('Content-Type: ' . feed_content_type('atom') . '; charset=' . get_option('blog_charset'), true);
 echo '<?xml version="1.0" encoding="' . get_option('blog_charset') . '" ?' . '>';
+do_action('atom_pre');
 ?>
 <feed
 	xmlns="http://www.w3.org/2005/Atom"
Index: wp-includes/feed-rss2-comments.php
===================================================================
--- wp-includes/feed-rss2-comments.php	(revision 19067)
+++ wp-includes/feed-rss2-comments.php	(working copy)
@@ -8,6 +8,7 @@
 header('Content-Type: ' . feed_content_type('rss-http') . '; charset=' . get_option('blog_charset'), true);
 
 echo '<?xml version="1.0" encoding="'.get_option('blog_charset').'"?'.'>';
+do_action('rss2_pre');
 ?>
 <rss version="2.0"
 	xmlns:content="http://purl.org/rss/1.0/modules/content/"