diff --git src/wp-comments-post.php src/wp-comments-post.php
index 0ed359c..a5cb0f5 100644
--- src/wp-comments-post.php
+++ src/wp-comments-post.php
@@ -47,7 +47,7 @@ if ( ! comments_open( $comment_post_ID ) ) {
 	 * @param int $comment_post_ID Post ID.
 	 */
 	do_action( 'comment_closed', $comment_post_ID );
-	wp_die( __('Sorry, comments are closed for this item.') );
+	wp_die( __('Sorry, comments are closed for this item.'), '', array( 'response' => 403 ) );
 } elseif ( 'trash' == $status ) {
 	/**
 	 * Fires when a comment is attempted on a trashed post.
@@ -112,20 +112,20 @@ if ( $user->exists() ) {
 	}
 } else {
 	if ( get_option('comment_registration') || 'private' == $status )
-		wp_die( __('Sorry, you must be logged in to post a comment.') );
+		wp_die( __('Sorry, you must be logged in to post a comment.'), '', array( 'response' => 403 ) );
 }
 
 $comment_type = '';
 
 if ( get_option('require_name_email') && !$user->exists() ) {
 	if ( 6 > strlen($comment_author_email) || '' == $comment_author )
-		wp_die( __('<strong>ERROR</strong>: please fill the required fields (name, email).') );
+		wp_die( __('<strong>ERROR</strong>: please fill the required fields (name, email).'), '', array( 'response' => 200 ) );
 	elseif ( !is_email($comment_author_email))
-		wp_die( __('<strong>ERROR</strong>: please enter a valid email address.') );
+		wp_die( __('<strong>ERROR</strong>: please enter a valid email address.'), '', array( 'response' => 200 ) );
 }
 
 if ( '' == $comment_content )
-	wp_die( __('<strong>ERROR</strong>: please type a comment.') );
+	wp_die( __('<strong>ERROR</strong>: please type a comment.'), '', array( 'response' => 200 ) );
 
 $comment_parent = isset($_POST['comment_parent']) ? absint($_POST['comment_parent']) : 0;
 
diff --git src/wp-includes/comment.php src/wp-includes/comment.php
index a4cc7e2..fed94df 100644
--- src/wp-includes/comment.php
+++ src/wp-includes/comment.php
@@ -843,7 +843,7 @@ function wp_allow_comment( $commentdata ) {
 		if ( defined( 'DOING_AJAX' ) ) {
 			die( __('Duplicate comment detected; it looks as though you&#8217;ve already said that!') );
 		}
-		wp_die( __('Duplicate comment detected; it looks as though you&#8217;ve already said that!') );
+		wp_die( __('Duplicate comment detected; it looks as though you&#8217;ve already said that!'), '', array('response' => 409) );
 	}
 
 	/**
@@ -960,7 +960,7 @@ function check_comment_flood_db( $ip, $email, $date ) {
 			if ( defined('DOING_AJAX') )
 				die( __('You are posting comments too quickly. Slow down.') );
 
-			wp_die( __('You are posting comments too quickly. Slow down.'), '', array('response' => 403) );
+			wp_die( __('You are posting comments too quickly. Slow down.'), '', array('response' => 429) );
 		}
 	}
 }