Problems getting case insensitive match to work

[Mario Gazzo]

I have for some reasons difficulties to get the following nginx setup  
to respond case insensitive to www.mydomain.dk/demo. It only responds  
to www.mydomain.dk/Demo. Shouldn't "~*" make the match case  
insensitive? The nginx reverseproxy server runs linux whereas the  
application server is Windows Server 2003 with IIS.

What am I doing wrong?

Cheers
Mario

worker_processes  1;

events {
     worker_connections  1024;
}

http {
     include    mime.types;
     include    proxy.conf;
     default_type  application/octet-stream;

     sendfile        on;
     keepalive_timeout  65;

     upstream demo_hosts {
           server  192.168.0.97:80;
   	}

server {
         listen 80;

         server_name  www.mydomain.dk;

         location ~* /Demo {
         	proxy_pass http://demo_hosts/Demo;
         }

     }
}