How to format dates based on locale?

[techy]

In a template I display the day and month of a specific date :\[code\]<div class="jour"><?php echo date('d',strtotime($content->getCreatedAt())) ?></div><div class="mois"><?php echo date('M',strtotime($content->getCreatedAt())) ?></div>\[/code\]This works fine, problem is the month name is in English. Where do I specify that I want the month names in another locale, French for instance ?