Nginx does not close socket

ngnix is not closing the socket after the connection finishes. I've googled and can't come up with anything to will tell nginx to close this connection, other than what I have below: keepalive_timeout 0.

In both the request and response headers, I can see Connection: close, but the socket still sits around in the TIME_WAIT state for about a minute.

tcp        0      0 127.0.0.1:80            127.0.0.1:40345         TIME_WAIT   -

Here are the headers:

Request Headers:
Connection: close
Content-Type: application/x-www-form-urlencoded

Response headers:
HTTP/1.1 200 OK
Server: nginx/0.7.67
Date: Thu, 21 Apr 2011 15:34:31 GMT
Content-Type: text/xml; charset=utf-8
Transfer-Encoding: chunked
Connection: close

Part of my nginx config:

nginx config file:

{
...
        keepalive_timeout 0;
        client_max_body_size 1M;
        fastcgi_read_timeout 60;
        fastcgi_send_timeout 60;

    location ~ \.php$ {
        fastcgi_pass   unix:/tmp/php-fastcgi.sock;
        #fastcgi_pass   127.0.0.1:9000;
        fastcgi_index  index.php;
        fastcgi_intercept_errors on; # to support 404s for PHP files not found
        fastcgi_param  SCRIPT_FILENAME $document_root$fastcgi_script_name;
        include        fastcgi_params;
        fastcgi_param SERVER_NAME $host;
    }
}