change month name to french
From http://php.net/manual/en/function.date.php:
To format dates in other languages, you should use the setlocale() and strftime() functions instead of date().
I know this is old but for anyone still looking this up, a more complete answer for your date in French would be:
//set locale
setlocale(LC_TIME, "fr_FR");
Then
//echo date/formatting based on your locale, in this case, for French
echo strftime("le %d %B, %Y", strtotime( $sgps_newsletter->getCreatedAt() ));
//without day of the week = le 18 septembre, 2013
OR
echo strftime("%A le %d %B, %Y", strtotime( $sgps_newsletter->getCreatedAt() ));
//with day of the week = mercredi le 18 septembre, 2013
OR
echo strftime("%d/%m/%Y", strtotime( $sgps_newsletter->getCreatedAt() ))
//numerical, separated by '/' = 18/9/2013
Use strftime
: http://php.net/manual/en/function.strftime.php
<?php
setlocale(LC_TIME, "fr_FR");
echo strftime(" in French %d.%M.%Y and");
(not sure about that %d.%M.%Y but you can read documentation)