Auth user with postgresql

[Giuseppe Tofoni]

Hi list
I am a nginx newbie.
Nginx does not ask user and password with the following configuration:
.......
   upstream database
    {
        postgres_server  127.0.0.1 dbname=dbnginx user=nginx password=secret;
    }

    server
    {
        listen       80;
        server_name  localhost;
        index  index.htm index.html;

        location =/t1
        {
            internal;

            postgres_escape   $user $remote_user;
            postgres_escape   $pass $remote_passwd;

            postgres_pass     database;
            postgres_query    "SELECT user  FROM usertable WHERE
user=$user AND pwd=$pass";
            postgres_rewrite  no_rows 403;
            postgres_output   none;
        }

        location /test       //don't request window for user and password
        {
            auth_basic  "folder test1";
            auth_request  /t1;
        }

        location /test2     //o.k. request window for user and password
        {
            auth_basic  "folder Test2";
            auth_basic_user_file  /web/test2/.passwd;
        }
-----------
I did several searches on google but found nothing.
Where is the mistake?
Thanks for the help

            Giuseppe

P.S: the database connection is ok  and password is stored in MD5
follow my compilation config

./configure \
  --prefix=/usr/local/nginx \
  --sbin-path=/usr/local/nginx/sbin/nginx \
  --conf-path=/etc/nginx/nginx.conf \
  --error-log-path=/var/log/nginx/error.log \
  --pid-path=/var/run/nginx/nginx.pid  \
  --lock-path=/var/lock/nginx.lock \
  --http-uwsgi-temp-path=/var/tmp/nginx \
  --http-scgi-temp-path=/var/tmp/nginx \
  --user=nobody \
  --group=nobody \
  --with-ipv6 \
  --with-http_dav_module \
  --with-http_ssl_module \
  --with-http_flv_module \
  --with-http_gzip_static_module \
  --http-log-path=/var/log/nginx/access.log \
  --http-client-body-temp-path=/var/tmp/nginx/client/ \
  --http-proxy-temp-path=/var/tmp/nginx/proxy/ \
  --http-fastcgi-temp-path=/var/tmp/nginx/fcgi/ \
  --add-module=/home/mercurio/nginx/ngx_http_auth_request_module-a29d74804ff1 \
  --add-module=/home/mercurio/nginx/FRiCKLE-ngx_coolkit-cb99a0f \
  --add-module=/home/mercurio/nginx/agentzh-nginx-eval-module-09d7728 \
  --add-module=/home/mercurio/nginx/ngx_postgres-0.9