Why isn't this working?

nginx.log

# After shutting down the app servers, the clients (open browsers) get a dump
# of all messages which have been held back...and this is dumped out to the nginx log

2011/09/26 22:55:57 [error] 5042#0: *1 connect() failed (111: Connection refused) while
connecting to upstream, client: 204.51.3.162, server: somedomain.com, request:
"GET /stream/0D9A1580 HTTP/1.1", upstream: "http://127.0.0.1:5000/stream/0D9A1580",
host: "somedomain.com", referrer: "http://somedomain.com/tags/0D9A1580/"

somedomain.conf

$ nginx -v
nginx: nginx version: nginx/1.1.4

$ bundle exec thin -v 
thin 1.2.11 codename Bat-Shit Crazy

##### nginx config
upstream thin {
        keepalive 1;
	server 127.0.0.1:5000;
	server 127.0.0.1:5001;
	server 127.0.0.1:5002;
}

server {
	server_name somedomain;
	root /opt/somedomain/website/public;
	access_log /var/log/nginx/somedomain-access.log;
	error_log /var/log/nginx/somedomain-error.log;
	rewrite_log on;

	# Set the max size for file uploads to 50Mb
	client_max_body_size 50M;

	location / {
		try_files $uri $uri/ @appservers;
	}

	location @appservers {
		proxy_http_version 1.1;
		proxy_set_header Connection "";
		proxy_pass http://thin;
	}

	location ~ ^/(images|javascripts|stylesheets|system)/  {
		expires max;
	}

	#error_page   500 502 503 504  /500.html;
}

Updated nginx config