Index: trunk/core/kernel/session/session.php
===================================================================
diff -u -r2785 -r2819
--- trunk/core/kernel/session/session.php	(.../session.php)	(revision 2785)
+++ trunk/core/kernel/session/session.php	(.../session.php)	(revision 2819)
@@ -309,18 +309,19 @@
 
 	function IsHTTPSRedirect()
 	{
+		$http_referer = getArrayValue($_SERVER, 'HTTP_REFERER');
 		return (
-						(PROTOCOL == 'https://' && preg_match('#http:\/\/#', $_SERVER['HTTP_REFERER']))
-						||
-						(PROTOCOL == 'http://' && preg_match('#https:\/\/#', $_SERVER['HTTP_REFERER']))
-					);
+					( PROTOCOL == 'https://' && preg_match('#http:\/\/#', $http_referer) )
+					||
+					( PROTOCOL == 'http://' && preg_match('#https:\/\/#', $http_referer) )
+				);
 	}
 
 	function CheckReferer()
 	{
 		$path = preg_replace("/admin$/", '', $this->CookiePath); // removing /admin for compatability with in-portal (in-link/admin/add_link.php)
 		$reg = '#^'.preg_quote(PROTOCOL.ltrim($this->CookieDomain, '.').$path).'#';
-		return preg_match($reg, $_SERVER['HTTP_REFERER']) || (defined('IS_POPUP') && IS_POPUP);
+		return preg_match($reg, getArrayValue($_SERVER, 'HTTP_REFERER') ) || (defined('IS_POPUP') && IS_POPUP);
 	}
 
 	function CheckIfCookiesAreOn()
Index: trunk/core/units/categories/categories_config.php
===================================================================
diff -u -r2284 -r2819
--- trunk/core/units/categories/categories_config.php	(.../categories_config.php)	(revision 2284)
+++ trunk/core/units/categories/categories_config.php	(.../categories_config.php)	(revision 2819)
@@ -79,7 +79,12 @@
 									            'PopItem' => Array('type' => 'int','not_null' => '1','default' => '2'),
 									            'Modified' => Array('type' => 'int','not_null' => '1','default' => '0'),
 									            'ModifiedById' => Array('type' => 'int','not_null' => '1','default' => '0'),
-									        ),							    
+									        ),
+									        
+					'VirtualFields'		=>	Array(
+													'CurrentSort'	=>	Array('type' => 'string', 'default' => ''),
+											),
+										
 					'Grids'	=> Array(
 								'Default'		=>	Array(
 																	'Icons' => Array('default'=>'icon16_cat.gif'),
Index: trunk/kernel/units/categories/categories_config.php
===================================================================
diff -u -r2284 -r2819
--- trunk/kernel/units/categories/categories_config.php	(.../categories_config.php)	(revision 2284)
+++ trunk/kernel/units/categories/categories_config.php	(.../categories_config.php)	(revision 2819)
@@ -79,7 +79,12 @@
 									            'PopItem' => Array('type' => 'int','not_null' => '1','default' => '2'),
 									            'Modified' => Array('type' => 'int','not_null' => '1','default' => '0'),
 									            'ModifiedById' => Array('type' => 'int','not_null' => '1','default' => '0'),
-									        ),							    
+									        ),
+									        
+					'VirtualFields'		=>	Array(
+													'CurrentSort'	=>	Array('type' => 'string', 'default' => ''),
+											),
+										
 					'Grids'	=> Array(
 								'Default'		=>	Array(
 																	'Icons' => Array('default'=>'icon16_cat.gif'),