Whenever you need to manipulate date/time stamps based on locale, you should use strftime
also change the encoding to utf-8
http://php.net/manual/en/function.strftime.php
example :
<?php
header('Content-Type: text/html; charset=UTF-8');
$myDate = "Feb 21, 2013";
$locale = 'fr_FR.utf8';
setlocale(LC_ALL, $locale);
echo strftime('%d %B %Y', strtotime($myDate));
$locale = 'en_US.utf8';
setlocale(LC_ALL, $locale);
echo strftime('%d %B %Y', strtotime($myDate));
?>