Index: wp-includes/feed-rss2-comments.php
===================================================================
--- wp-includes/feed-rss2-comments.php	(revision 15241)
+++ wp-includes/feed-rss2-comments.php	(working copy)
@@ -18,12 +18,14 @@
 	>
 <channel>
 	<title><?php
+		$head_title = '';
 		if ( is_singular() )
-			printf(ent2ncr(__('Comments on: %s')), get_the_title_rss());
+			$head_title = sprintf(ent2ncr(__('Comments on: %s')), get_the_title_rss());
 		elseif ( is_search() )
-			printf(ent2ncr(__('Comments for %s searching on %s')), get_bloginfo_rss( 'name' ), esc_attr($wp_query->query_vars['s']));
+			$head_title = sprintf(ent2ncr(__('Comments for %s searching on %s')), get_bloginfo_rss( 'name' ), esc_attr($wp_query->query_vars['s']));
 		else
-			printf(ent2ncr(__('Comments for %s')), get_bloginfo_rss( 'name' ) . get_wp_title_rss());
+			$head_title = sprintf(ent2ncr(__('Comments for %s')), get_bloginfo_rss( 'name' ) . get_wp_title_rss());
+		echo apply_filters('commentsrss2_head_title',$head_title);
 	?></title>
 	<atom:link href="<?php self_link(); ?>" rel="self" type="application/rss+xml" />
 	<link><?php (is_single()) ? the_permalink_rss() : bloginfo_rss("url") ?></link>
@@ -39,13 +41,15 @@
 ?>
 	<item>
 		<title><?php
+			$item_title = '';
 			if ( !is_singular() ) {
 				$title = get_the_title($comment_post->ID);
 				$title = apply_filters('the_title_rss', $title);
-				printf(ent2ncr(__('Comment on %1$s by %2$s')), $title, get_comment_author_rss());
+				$item_title = sprintf(ent2ncr(__('Comment on %1$s by %2$s')), $title, get_comment_author_rss());
 			} else {
-				printf(ent2ncr(__('By: %s')), get_comment_author_rss());
+				$item_title = sprintf(ent2ncr(__('By: %s')), get_comment_author_rss());
 			}
+			echo apply_filters('commentrss2_item_title', $item_title, $comment);
 		?></title>
 		<link><?php comment_link() ?></link>
 		<dc:creator><?php echo get_comment_author_rss() ?></dc:creator>