How to change default date language?

[hameau]

Code:

<?php get_page_date(); ?>

You can do it with strftime function. If you change your snippet to this:

Code:

<?php echo strftime("%A, %e %B, %Y",get_page_date('U',false)); ?>

you will get the date according to the PHP locale set in gsconfig.php.

For example:
en_GB: Wednesday, 29 October, 2014
fr_FR: mercredi, 29 octobre, 2014

get_page_date('U',false) returns (instead of echo) the date in Unix epoch format, which is then changed to the locale-specific format by strftime.

See the PHP manual for strftime for all the formatting options.