now it works!
I’m using Nginx and FastCGI and looked at the server error log:
tail /var/log/nginx/error.log
”
2014/04/18 05:52:25 [error] 22164#0: *1306 FastCGI sent in stderr: “PHP message: PHP Fatal error: Call to undefined function curl_init() in /…/wp-content/themes/kleo/kleo-framework/options/inc/fields/typography/field_typography.php on line 221″ while reading upstream,…
”
found out, that I didn’t install php5-curl (how silly of me 🙂 )
I did the following:
sudo apt-get update
sudo apt-get install curl libcurl3 libcurl3-dev php5-curl
sudo /etc/init.d/php5-fpm restart