date(): It is not safe to rely on the system's timezone settings.
In my httpd error log I have the following message from time to time:
PHP Strict Standards: date(): It is not safe to rely on the system's timezone settings. Please use the date.timezone setting, the TZ environment variable or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected 'Europe/Berlin' for 'CET/1.0/no DST' instead in /usr/local/ispconfig/interface/lib/classes/session.inc.php on line 113
It is not something urgent but I think it makes sense if somewhere in the bootstrap the timezone is set with date_default_timezone_set(). This way less people will ask what is happening here.