Index: branches/5.0.x/core/kernel/application.php
===================================================================
diff -u -N -r12953 -r12970
--- branches/5.0.x/core/kernel/application.php	(.../application.php)	(revision 12953)
+++ branches/5.0.x/core/kernel/application.php	(.../application.php)	(revision 12970)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: application.php 12953 2009-12-20 12:51:32Z alex $
+* @version	$Id: application.php 12970 2009-12-22 11:02:37Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -245,13 +245,12 @@
 	{
 		static $instance = false;
 
-		if(!$instance)
-		{
-			safeDefine('APPLICATION_CLASS', 'kApplication');
-			$class = APPLICATION_CLASS;
+		if (!$instance) {
+			$class = defined('APPLICATION_CLASS') ? APPLICATION_CLASS : 'kApplication';
 			$instance = new $class();
 			$instance->Application =& $instance;
 		}
+
 		return $instance;
 	}
 
@@ -566,22 +565,30 @@
 		return $path;
 	}
 
-	function GetDefaultLanguageId()
+	function GetDefaultLanguageId($init = false)
 	{
-		static $language_id = 0;
+		static $language_info = null;
 
-		if ($language_id > 0) {
-			return $language_id;
+		if (!isset($language_info)) {
+			// cache primary language info first
+			$table = $this->getUnitOption('lang', 'TableName');
+			$id_field = $this->getUnitOption('lang', 'IDField');
+
+			$sql = 'SELECT ' . $id_field . ', IF(AdminInterfaceLang, "Admin", "Front") AS LanguageKey
+					FROM ' . $table . '
+					WHERE (AdminInterfaceLang = 1 OR PrimaryLang = 1) AND (Enabled = 1)';
+			$language_info = $this->Conn->GetCol($sql, 'LanguageKey');
 		}
 
-		$table = $this->getUnitOption('lang', 'TableName');
-		$id_field = $this->getUnitOption('lang', 'IDField');
+		$language_key = ($this->isAdmin && $init) || count($language_info) == 1 ? 'Admin' : 'Front';
 
-		$sql = 'SELECT '.$id_field.'
-				FROM '.$table.'
-				WHERE (PrimaryLang = 1) AND (Enabled = 1)';
-		$language_id = $this->Conn->GetOne($sql);
+		if (array_key_exists($language_key, $language_info) && $language_info[$language_key] > 0) {
+			// get from cache
+			return $language_info[$language_key];
+		}
 
+		$language_id = $language_info && array_key_exists($language_key, $language_info) ? $language_info[$language_key] : false;
+
 		if (!$language_id && defined('IS_INSTALL') && IS_INSTALL) {
 			$language_id = 1;
 		}