$_SERVER['PATH_INFO'] variable unicode problem.

[eluser]FutureKing[/eluser]
I am using PHP5 on Windows Server 2008.

I created a small script to test $_SERVER['PATH_INFO'] variable.

=========
<?php
header('Content-type: text/html; charset=utf-8');
echo $_SERVER['PATH_INFO'];
========

I uploaded it on example.com/test.php

If I request http://example.com/test.php/someword/anotherword
then I get this output
========


/someword/anotherword


========

If I request http://example.com/test.php/कुछशब्द/कुछऔरशब्द/english
then I get this output
========


/???????/?????????/english


========

Notice the "?????" in above output.

Why PATH_INFO is it not supporting hindi chars? Why is it producing "???????" for hindi chars?