merge r25094 to release-1.12

git-svn-id: http://framework.zend.com/svn/framework/standard/branches/release-1.12@25095 44c647ce-9c0f-0410-b52a-842ac1e357ba

library/Zend/Debug.php

@@ -90,7 +90,12 @@ class Zend_Debug
                     . PHP_EOL;
         } else {
             if(!extension_loaded('xdebug')) {
-                $output = htmlspecialchars($output, ENT_QUOTES);
+                $flags = ENT_QUOTES;
+                // PHP 5.4.0+
+                if (defined('ENT_SUBSTITUTE')) {
+                    $flags = ENT_QUOTES | ENT_SUBSTITUTE;
+                }
+                $output = htmlspecialchars($output, $flags);
             }
 
             $output = '<pre>'