diff --git a/wp-comments-post.php b/wp-comments-post.php
index 0fc2317544..64cc8e3295 100644
--- a/wp-comments-post.php
+++ b/wp-comments-post.php
@@ -40,6 +40,8 @@ $comment_content      = ( isset($_POST['comment']) ) ? trim($_POST['comment']) :
 // If the user is logged in
 $user = wp_get_current_user();
 if ( $user->ID ) {
+	if ( empty( $user->display_name ) )
+		$user->display_name=$user->user_login;
 	$comment_author       = $wpdb->escape($user->display_name);
 	$comment_author_email = $wpdb->escape($user->user_email);
 	$comment_author_url   = $wpdb->escape($user->user_url);
diff --git a/wp-includes/comment-template.php b/wp-includes/comment-template.php
index fba653c0b4..75cf57c229 100644
--- a/wp-includes/comment-template.php
+++ b/wp-includes/comment-template.php
@@ -21,10 +21,16 @@
  */
 function get_comment_author() {
 	global $comment;
-	if ( empty($comment->comment_author) )
-		$author = __('Anonymous');
-	else
+	if ( empty($comment->comment_author) ) {
+		if (!empty($comment->user_id)){
+			$user=get_userdata($comment->user_id);
+			$author=$user->user_login;
+		} else {
+			$author = __('Anonymous');
+		}
+	} else {
 		$author = $comment->comment_author;
+	}
 	return apply_filters('get_comment_author', $author);
 }