Markus,
If you still have a problem, check this out:
https://www.howtoforge.com/community/threads/ispconfig-3-and-owncloud-nginx-ceontos-6-5-on-vps.68139/#post-324306
It helped me out.
I'm running ISPconfig 3 with nginx on CentOS 6.5
If you still have a problem, check this out:
https://www.howtoforge.com/community/threads/ispconfig-3-and-owncloud-nginx-ceontos-6-5-on-vps.68139/#post-324306
It helped me out.
I'm running ISPconfig 3 with nginx on CentOS 6.5