root/trunk/wp-includes/feed-atom-comments.php

<?php
/**
 * Atom Feed Template for displaying Atom Comments feed.
 *
 * @package WordPress
 */

header('Content-Type: application/atom+xml; charset=' . get_option('blog_charset'), true);
echo '<?xml version="1.0" encoding="' . get_option('blog_charset') . '" ?' . '>';
?>
<feed
    xmlns="http://www.w3.org/2005/Atom"
    xml:lang="<?php echo get_option('rss_language'); ?>"
    <?php do_action('atom_ns'); ?>
>
    <title type="text"><?php
        if ( is_singular() )
            printf(__('Comments on: %s'), get_the_title_rss());
        elseif ( is_search() )
            printf(__('Comments for %1$s searching on %2$s'), get_bloginfo_rss( 'name' ), attribute_escape(get_search_query()));
        else
            printf(__('Comments for %s'), get_bloginfo_rss( 'name' ) . get_wp_title_rss());
    ?></title>
    <subtitle type="text"><?php bloginfo_rss('description'); ?></subtitle>

    <updated><?php echo mysql2date('Y-m-d\TH:i:s\Z', get_lastcommentmodified('GMT')); ?></updated>
    <?php the_generator( 'atom' ); ?>

<?php if ( is_singular() ) { ?>
    <link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php echo get_comments_link(); ?>" />
    <link rel="self" type="application/atom+xml" href="<?php echo get_post_comments_feed_link('', 'atom'); ?>" />
    <id><?php echo get_post_comments_feed_link('', 'atom'); ?></id>
<?php } elseif(is_search()) { ?>
    <link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php echo get_option('home') . '?s=' . attribute_escape(get_search_query()); ?>" />
    <link rel="self" type="application/atom+xml" href="<?php echo get_search_comments_feed_link('', 'atom'); ?>" />
    <id><?php echo get_search_comments_feed_link('', 'atom'); ?></id>
<?php } else { ?>
    <link rel="alternate" type="<?php bloginfo_rss('html_type'); ?>" href="<?php bloginfo_rss('home'); ?>" />
    <link rel="self" type="application/atom+xml" href="<?php bloginfo_rss('comments_atom_url'); ?>" />
    <id><?php bloginfo_rss('comments_atom_url'); ?></id>
<?php } ?>

<?php
if ( have_comments() ) : while ( have_comments() ) : the_comment();
    $comment_post = get_post($comment->comment_post_ID);
    get_post_custom($comment_post->ID);
?>
    <entry>
        <title><?php
            if ( !is_singular() ) {
                $title = get_the_title($comment_post->ID);
                $title = apply_filters('the_title_rss', $title);
                printf(__('Comment on %1$s by %2$s'), $title, get_comment_author_rss());
            } else {
                printf(__('By: %s'), get_comment_author_rss());
            }
        ?></title>
        <link rel="alternate" href="<?php comment_link(); ?>" type="<?php bloginfo_rss('html_type'); ?>" />

        <author>
            <name><?php comment_author_rss(); ?></name>
            <?php if (get_comment_author_url()) echo '<uri>' . get_comment_author_url() . '</uri>'; ?>

        </author>

        <id><?php comment_link(); ?></id>
        <updated><?php echo mysql2date('Y-m-d\TH:i:s\Z', get_comment_time('Y-m-d H:i:s', true), false); ?></updated>
        <published><?php echo mysql2date('Y-m-d\TH:i:s\Z', get_comment_time('Y-m-d H:i:s', true), false); ?></published>
<?php if (!empty($comment_post->post_password) && $_COOKIE['wp-postpass'] != $comment_post->post_password) : ?>
        <content type="html" xml:base="<?php comment_link(); ?>"><![CDATA[<?php echo get_the_password_form(); ?>]]></content>
<?php else : // post pass ?>
        <content type="html" xml:base="<?php comment_link(); ?>"><![CDATA[<?php comment_text(); ?>]]></content>
<?php endif; // post pass
    do_action('comment_atom_entry', $comment->comment_ID, $comment_post->ID);
?>
    </entry>
<?php endwhile; endif; ?>
</feed>