Replacing apache with nginx

[Stephen Nelson-Smith]

I have apache 2.2 load-balancing a pool of 3 tomcat servers.  I want
to replace it with nginx.  I have the following very simple setup to
test the concept:

user  nginx;
worker_processes  2;

error_log  logs/error.log debug;

pid        logs/nginx.pid;

events {
    worker_connections  1024;
}

http {
    default_type  application/octet-stream;

    log_format  main  '$remote_addr - $remote_user [$time_local] $status '
                      '"$request" $body_bytes_sent "$http_referer" '
                      '"$http_user_agent" "http_x_forwarded_for"';

    access_log  logs/access.log  main;

    sendfile        on;
    tcp_nopush     on;
    tcp_nodelay    on;

    server {
        listen       80;
        server_name  www.mysite.dmz;
        large_client_header_buffers 4 16k;

        access_log  logs/host.access.log  main;

        # Main location
        location / {
            proxy_pass         http://10.1.1.241:8080/;
            proxy_redirect     off;

            proxy_set_header   Host             $host;
            proxy_set_header   X-Real-IP        $remote_addr;
            proxy_set_header   X-Forwarded-For  $proxy_add_x_forwarded_for;

            client_max_body_size       10m;
            client_body_buffer_size    128k;

            proxy_connect_timeout      90;
            proxy_send_timeout         90;
            proxy_read_timeout         90;

            proxy_buffer_size          4k;
            proxy_buffers              4 32k;
            proxy_busy_buffers_size    64k;
            proxy_temp_file_write_size 64k;
        }

    }
}

This seems to work ok, although I've not yet looked up what each thing
does.  What I need it to do, which I had some problems doing with
apache is the following:

1) Needs to loadbalance over 3 servers
2) Sessions need to be sticky - so the user goes to the same server
all the time, after the session is started.
3) All http traffic needs to be coerced to https apart from www.mysite.com/xml

Any pointers to example configs or bits of the documentation would be
most welcome.  I'm just diving into the wiki now, but and handy
pointers would be a great help.

Thanks,

S.