Index: wp-includes/default-widgets.php
===================================================================
--- wp-includes/default-widgets.php	(revision 11812)
+++ wp-includes/default-widgets.php	(working copy)
@@ -633,21 +633,20 @@
 		else if ( $number > 15 )
 			$number = 15;
 
-		if ( !$comments = wp_cache_get( 'recent_comments', 'widget' ) ) {
-			$comments = $wpdb->get_results("SELECT * FROM $wpdb->comments WHERE comment_approved = '1' ORDER BY comment_date_gmt DESC LIMIT 15");
-			wp_cache_add( 'recent_comments', $comments, 'widget' );
-		}
+		$comments = get_comments(array('number' => $number));
 
-		$comments = array_slice( (array) $comments, 0, $number );
-?>
-		<?php echo $before_widget; ?>
-			<?php if ( $title ) echo $before_title . $title . $after_title; ?>
-			<ul id="recentcomments"><?php
-			if ( $comments ) : foreach ( (array) $comments as $comment) :
-			echo  '<li class="recentcomments">' . /* translators: comments widget: 1: comment author, 2: post link */ sprintf(_x('%1$s on %2$s', 'widgets'), get_comment_author_link(), '<a href="' . esc_url( get_comment_link($comment->comment_ID) ) . '">' . get_the_title($comment->comment_post_ID) . '</a>') . '</li>';
-			endforeach; endif;?></ul>
-		<?php echo $after_widget; ?>
-<?php
+		echo $before_widget;
+		if ( $title ) 
+			echo $before_title . $title . $after_title;
+
+		echo '<ul id="recentcomments">';
+		if ( $comments ) { 
+			foreach ( (array) $comments as $comment) {
+				echo  '<li class="recentcomments">' . /* translators: comments widget: 1: comment author, 2: post link */ sprintf(_x('%1$s on %2$s', 'widgets'), get_comment_author_link(), '<a href="' . esc_url( get_comment_link($comment->comment_ID) ) . '">' . get_the_title($comment->comment_post_ID) . '</a>') . '</li>';
+			}
+		}
+		echo '</ul>';
+		echo $after_widget;
 	}
 
 	function update( $new_instance, $old_instance ) {