Description:
------------
I would like to do backward compatibility in namespace code.

Reproduce code:
---------------
<?php

if ( (float) substr(phpversion(),0,3) >= 5.3)
namespace MySpace\SubSpace;

?>
<?

if ( (float) substr(phpversion(),0,3) >= 5.3)
use MySpace\SubSpace\MyClass;

?>

Expected result:
----------------
In PHP >= 5.3... All classes are in \MySpace\SubSpace
In PHP < 5.3... All classes are in global Space \


Actual result:
--------------
Parse error: parse error, expecting `T_NS_SEPARATOR' in space.lib.php on line 3