PHP below server root not served

[nano]

I am having trouble configuring nginx to serve up PHP from outside of 
the server document root. For example, this site's root is 
/usr/local/www/site1/wordpress and phpMyAdmin is located in 
/usr/local/www/phpMyAdmin. I cannot access servername.com/phpmyadmin. 
nginx logs the following error:

====================================================================
2014/01/09 09:56:20 [error] 39387#0: *6160 FastCGI sent in stderr: 
"Primary script unknown" while reading response header from upstream, 
client: clientIP, server: serverhostname, request: "GET /phpmyadmin/ 
HTTP/1.1", upstream: "fastcgi://unix:/var/run/php-fpm.sock:", host: 
"serverhostname"
====================================================================

The WordPress site, however, is served without error. Therefore, nginx 
is refusing to serve PHP from outside of the server document root. 
Please see the following configuration:


nginx.conf
====================================================================
user  www www;
worker_processes 1;
pid /var/run/nginx.pid;
error_log  logs/error.log  info;

events {
     worker_connections  768;
     use kqueue;
}

http {
     include       mime.types;
     default_type  application/octet-stream;

     access_log  logs/access.log  main;
     sendfile        on;
     keepalive_timeout  65;
     gzip  on;

server {
         listen 80;
         listen 443 ssl;
         server_name servername.com;
         ssl_certificate crt-chain.pem;
         ssl_certificate_key key.pem;
         ssl_dhparam dhparam4096.pem;
         ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
         ssl_ciphers "EECDH+ECDSA+AESGCM EECDH+aRSA+AESGCM 
EECDH+ECDSA+SHA384 EECDH+ECDSA+SHA256 EECDH+aRSA+SHA384 
EECDH+aRSA+SHA256 EECDH+aRSA+RC4 EECDH EDH+aRSA RC4 !a
NULL !eNULL !LOW !3DES !MD5 !EXP !PSK !SRP !DSS !RC4";
         ssl_prefer_server_ciphers on;

         root /usr/local/www/site1/wordpress;
         index index.php;

         location / {
                 try_files $uri $uri/ /index.php?$args;
         }

         location ~ \.php$ {
                 fastcgi_pass unix:/var/run/php-fpm.sock;
                 fastcgi_param SCRIPT_FILENAME 
/usr/local/www/site1/wordpress$fastcgi_script_name;
                 fastcgi_param PATH_INFO $fastcgi_script_name;
                 include fastcgi_params;
         }

#----------------------PROBLEM AREA----------------------#

         location /phpmyadmin/ {
             alias       /usr/local/www/phpMyAdmin/;
             index index.php index.html;
         }

         location ~ ^/phpmyadmin/(.*\.php)$ {
             fastcgi_param PHP_ADMIN_VALUE 
open_basedir=/usr/local/www/phpMyAdmin;
             fastcgi_pass        unix:/tmp/php-fpm.sock;
             fastcgi_index index.php;
             fastcgi_param SCRIPT_FILENAME 
/usr/local/www/phpMyAdmin$fastcgi_script_name;
             include fastcgi_params;

#----------------------PROBLEM AREA----------------------#

         }
     }
}
====================================================================


I am obviously lacking some required configuration. Perhaps in 
nginx.conf, php-fpm.conf, or php.ini. Could someone please advise me of 
my error and how to correct it? Thank you.

Strangely, in Apache, I simply required an alias entry, such as:

Alias /phpmyadmin "/usr/local/www/phpMyAdmin"
<Directory "/usr/local/www/phpMyAdmin">
   Options None
         AllowOverride None
         Require all granted
</Directory>

in my httpd.conf file even when the server root was above this location 
and with the exact same PHP settings (php.ini) as I now have with nginx.

Server intel:
# uname -a
FreeBSD hostname 9.2-RELEASE FreeBSD 9.2-RELEASE #0 r255898: Thu Sep 26 
22:50:31 UTC 2013 
root at bake.isc.freebsd.org:/usr/obj/usr/src/sys/GENERIC  amd64

# nginx -V
nginx version: nginx/1.5.7
TLS SNI support enabled
configure arguments: --prefix=/usr/local/etc/nginx --with-cc-opt='-I 
/usr/local/include' --with-ld-opt='-L /usr/local/lib' 
--conf-path=/usr/local/etc/nginx/nginx.conf 
--sbin-path=/usr/local/sbin/nginx --pid-path=/var/run/nginx.pid 
--error-log-path=/var/log/nginx-error.log --user=www --group=www 
--with-ipv6 --with-google_perftools_module 
--http-client-body-temp-path=/var/tmp/nginx/client_body_temp 
--http-fastcgi-temp-path=/var/tmp/nginx/fastcgi_temp 
--http-proxy-temp-path=/var/tmp/nginx/proxy_temp 
--http-scgi-temp-path=/var/tmp/nginx/scgi_temp 
--http-uwsgi-temp-path=/var/tmp/nginx/uwsgi_temp 
--http-log-path=/var/log/nginx-access.log --with-http_addition_module 
--with-http_auth_request_module --with-http_dav_module 
--with-http_flv_module --with-http_geoip_module 
--with-http_gzip_static_module --with-http_gunzip_module 
--with-http_image_filter_module --with-http_mp4_module 
--with-http_perl_module --with-http_random_index_module 
--with-http_realip_module --with-http_secure_link_module 
--with-http_stub_status_module --with-http_sub_module 
--with-http_xslt_module --with-pcre --with-http_spdy_module --with-mail 
--with-mail_ssl_module --with-http_ssl_module


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