You'll have to change these values in the locale pack file "locale.php": $Definition['Date.DefaultDayFormat'] = '%e. %B'; $Definition['Date.DefaultFormat'] = '%e. %B %Y'; $Definition['Date.DefaultTimeFormat'] = '%H:%M'; This example is for the german date format. You can find the full documentation for the variables you can use here: http://php.net/manual/de/function.strftime.php
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$Definition['Date.DefaultDayFormat'] = '%e. %B';
$Definition['Date.DefaultFormat'] = '%e. %B %Y';
$Definition['Date.DefaultTimeFormat'] = '%H:%M';
This example is for the german date format. You can find the full documentation for the variables you can use here: http://php.net/manual/de/function.strftime.php