Index: wp-admin/includes/class-wp-comments-list-table.php
===================================================================
--- wp-admin/includes/class-wp-comments-list-table.php	(revision 18555)
+++ wp-admin/includes/class-wp-comments-list-table.php	(working copy)
@@ -311,7 +311,7 @@
 
 		$this->user_can = current_user_can( 'edit_comment', $comment->comment_ID );
 
-		echo "<tr id='comment-$comment->comment_ID' class='$the_comment_status'>";
+		echo "<tr id='comment-$comment->comment_ID' class='" . join( ' ', get_comment_class( $the_comment_status ) ) . "'>";
 		echo $this->single_row_columns( $comment );
 		echo "</tr>";
 	}