diff --git a/library/includes/functions.php b/library/includes/functions.php
index e08a54f2..907b7ac5 100644
--- a/library/includes/functions.php
+++ b/library/includes/functions.php
@@ -1864,12 +1864,6 @@ function bb_die ($msg_text)
 	exit;
 }
 
-// Alias for bb_die()
-function message_die ($msg_code, $msg_text = '')
-{
-	bb_die($msg_text);
-}
-
 function bb_simple_die ($txt)
 {
 	global $bb_cfg;
@@ -1883,6 +1877,19 @@ function bb_simple_die ($txt)
 	die($txt);
 }
 
+// Alias for bb_die()
+function message_die ($msg_code, $msg_text = '')
+{
+	if ($msg_code == CRITICAL_MESSAGE || $msg_code == CRITICAL_ERROR)
+	{
+		bb_simple_die($msg_text);
+	}
+	else
+	{
+		bb_die($msg_text);
+	}
+}
+
 function bb_realpath ($path)
 {
 	return (!@function_exists('realpath') || !@realpath(INC_DIR . 'functions.php')) ? $path : @realpath($path);
diff --git a/library/includes/init_bb.php b/library/includes/init_bb.php
index fdf5c10e..8069c280 100644
--- a/library/includes/init_bb.php
+++ b/library/includes/init_bb.php
@@ -122,6 +122,12 @@ define('SEARCH_TYPE_TRACKER',  1);
 define('E_AJAX_GENERAL_ERROR', 1000);
 define('E_AJAX_NEED_LOGIN',    1001);
 
+// Error codes (Legacy)
+define('GENERAL_MESSAGE',      200);
+define('GENERAL_ERROR',        202);
+define('CRITICAL_MESSAGE',     203);
+define('CRITICAL_ERROR',       204);
+
 // Private messaging
 define('PRIVMSGS_READ_MAIL',      0);
 define('PRIVMSGS_NEW_MAIL',       1);