first of all thank you for your answers.
Maybe I didn't explain it very clearly.
I've a domain let's say example.com, on my webserver the hostname is srv.example.com (it should point to /usr/share/nginx/www which is described in vHost for "default"). Also the IP (123.456.678.9) should point to this directory, but it doesn't.
It points to the web from a client. And that since I've assigned the IP via control panel at the "sites" tab to this customer before. So I didn't choose wildcard but exactly this IP.
After I removed this - because I thought this will give the IP private to the customer - I noted that the IP (123.456.678.9) - which pointed correctly to the nginx ww before, shows now the web of the client.
I don't have that IP listed as server IP, because I want to have this IP pointing to the nginx-ww like hostname (srv.example.com) and all other IPs which are pointing to that server but not assigned to any customers.
But they all point to the web from this one client... I really don't know why. I followed the installation tutorial step by step.
Last edited by error.log; 15th August 2012 at 13:44.