getting remot4e address

[rkmr.em at gmail.com]

hi
i have haproxy running in front of nginx, and i have the
x-forwarded-for enabled in the haproxy configuration.
How do I configure nginx so that my fastcgi backends get this IP
address as the remote ip address and not the ip address of the
haproxy.

these are my fastcgi parameters

            fastcgi_param SCRIPT_FILENAME $fastcgi_script_name;
            fastcgi_param PATH_INFO       $fastcgi_script_name;
            fastcgi_param QUERY_STRING    $query_string;
            fastcgi_param CONTENT_TYPE    $content_type;
            fastcgi_param CONTENT_LENGTH  $content_length;
            fastcgi_param REQUEST_METHOD  $request_method;
            fastcgi_param REMOTE_ADDR     $remote_addr;
            fastcgi_param REMOTE_PORT     $remote_port;
            fastcgi_param SERVER_PROTOCOL $server_protocol;
            fastcgi_param SERVER_ADDR     $server_addr;
            fastcgi_param SERVER_PORT     $server_port;
            fastcgi_param SERVER_NAME     $server_name;