Index: branches/5.3.x/core/install/prerequisites.php
===================================================================
diff -u -r15483 -r15677
--- branches/5.3.x/core/install/prerequisites.php	(.../prerequisites.php)	(revision 15483)
+++ branches/5.3.x/core/install/prerequisites.php	(.../prerequisites.php)	(revision 15677)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: prerequisites.php 15237 2012-03-26 16:52:18Z alex $
+* @version	$Id: prerequisites.php 15677 2013-01-17 18:52:50Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -118,7 +118,15 @@
 		{
 			$ret = Array ();
 			$ret['php_version'] = version_compare(PHP_VERSION, '5.2.0', '>=');
-			$ret['url_rewriting'] = function_exists('apache_get_modules') && in_array('mod_rewrite', apache_get_modules());
+
+			if ( function_exists('apache_get_modules') ) {
+				$mod_rewrite = in_array('mod_rewrite', apache_get_modules());
+			}
+			else {
+				$mod_rewrite = getenv('HTTP_MOD_REWRITE') == 'On';
+			}
+
+			$ret['url_rewriting'] = $mod_rewrite;
 			$ret['memcache'] = class_exists('Memcache');
 			$ret['curl'] = function_exists('curl_init');
 			$ret['simplexml'] = function_exists('simplexml_load_string');
@@ -144,14 +152,30 @@
 			$ret['display_errors'] = $this->isPhpSettingChangeable('display_errors', '1');
 			$ret['error_reporting'] = $this->canChangeErrorReporting();
 			$ret['date.timezone'] = ini_get('date.timezone') != '';
+			$ret['variables_order'] = $this->_hasLetters(ini_get('variables_order'), Array ('G', 'P', 'C', 'S'));
 
-			$ret['variables_order'] = strpos(ini_get('variables_order'), 'GPC') !== false;
-			$ret['output_buffering'] = ini_get('output_buffering') > 0;
+			$output_buffering = strtolower(ini_get('output_buffering'));
+			$ret['output_buffering'] = $output_buffering == 'on' || $output_buffering > 0;
 
 			return $ret;
 		}
 
 		/**
+		 * Determines of a setting string has all given letters (ignoring order) in it
+		 *
+		 * @param string $setting
+		 * @param Array $search_letters
+		 * @return bool
+		 * @access protected
+		 */
+		protected function _hasLetters($setting, $search_letters)
+		{
+			$setting = preg_replace('/(' . implode('|', $search_letters) . ')/', '*', $setting);
+
+			return substr_count($setting, '*') == count($search_letters);
+		}
+
+		/**
 		 * Detects if error reporting can be changed at runtime
 		 *
 		 * @return bool