wordpress comment query

<?php get_header(); ?>

<ul class="double-cloumn clearfix">
    <li id="left-column">
        <ul class="blog-main-post-container">
<?php
$thisauthor = (get_query_var('author_name')) ? get_user_by('slug', get_query_var('author_name')) : get_userdata(get_query_var('author'));

?>
<div style="float: right;">
<? if(function_exists('get_avatar')) { echo get_avatar($thisauthor->user_email, 96, "" ); } ?> </div>

<h2><?php echo $thisauthor->first_name . " " . $thisauthor->last_name; ?> (<?php echo $thisauthor->display_name; ?>)</h2>
<p><a href="<? echo $thisauthor->user_url; ?>"><? echo $thisauthor->user_url; ?></a><br />
<a href="mailto:<? echo $thisauthor->user_email; ?>">email</a>
<p><?php echo $thisauthor->description; ?> </p>

<?php if (have_posts()) : ?>
<h2>Recent Posts </h2>
<ul>
<? while (have_posts()) :  the_post();  ?>
		<li><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></li>

<?php endwhile; else: ?>
<li>This user hasn't published any posts. </li>
<?php endif;  ?>
</ul>

<?php
$some_email = $thisauthor->user_email;
$querystr = "
    SELECT  comment_ID, comment_post_ID, comment_content, post_title
    FROM $wpdb->comments, $wpdb->posts
    WHERE comment_author_email = '$some_email'
    AND comment_approved = 1
	GROUP BY comment_ID
    ORDER BY comment_ID DESC
 ";
 $comments_array = $wpdb->get_results($querystr, OBJECT);

if ($comments_array): ?>
<h2>Recent Comments </h2>
<ul>
<? foreach ($comments_array as $comment):
	setup_postdata($comment);
	echo "<li><a href='". get_bloginfo('url') ."/?p=".$comment->comment_post_ID."'>Comment on ". $comment->post_title. "</a><br />". $comment->comment_content . "</li>";
endforeach; ?>
</ul>
<? endif; ?>
        </ul>

	</li>
</ul>
<?php get_footer(); ?>