PHP Error 500: Timezone database is corrupt – this should *never* happen

I have a fresh install of an Ubuntu Server 16.04 amd64 with apache 2.4.18 and php 7.0.

I have chrooted the Apache with mod_env and
ChrootDir /var/www
in /etc/apache2/apache2.conf and far as I know is here the problem. I want to do a NexctCloud 11 Installation, but on first run it runs into a 500 Error.

Apache Error Log:

[Fri Mar 17 08:21:22.262901 2017] [:error] [pid 31480] [client 193.175.51.226:55749] PHP Notice:  date_default_timezone_set(): Timezone ID 'UTC' is invalid in /html/sub.example.com/public_html/lib/base.php on line 637, referer: https://sub.example.com/
[Fri Mar 17 08:21:22.266581 2017] [:error] [pid 31480] [client 193.175.51.226:55749] PHP Warning:  DateTime::createFromFormat(): Invalid date.timezone value 'Europe/Berlin', we selected the timezone 'UTC' for now. in /html/sub.example.com/public_html/lib/private/Log/File.php on line 85, referer: https://sub.example.com/
[Fri Mar 17 08:21:22.266610 2017] [:error] [pid 31480] [client 193.175.51.226:55749] PHP Fatal error:  DateTime::createFromFormat(): Timezone database is corrupt - this should *never* happen! in /html/sub.example.com/public_html/lib/private/Log/File.php on line 85, referer: https://sub.example.com/

If I deactivate the Chroot, everything is fine, but I prefer a other solution where I dont have to deactivate the chroot.

I have found one suggestion on the web: http://ivanbayan.com/index.php/2013/06/26/how-to-fix-timezone-database-is-corrupt-this-should-never-happen/ which I have tryed out (customized for my php7), but it didnt solve the problem. Also I have tryed some suggestions from here without solving my problem: PHP Startup: Timezone database is corrupt

//Edit:
It seems that is not only a problem with NextCloud. It is a Problem using date() function in PHP. The following script resultes in the same error:

<?php
date_default_timezone_set('Europe/Berlin');

echo date("l");
?>