Configuring phpMyAdmin with nginx (Fedora 17) for access at localhost/phpmyadmin

For your 404, you should make the character cases match either all phpmyadmin (all lower case) or phpMyAdmin.

To make the config clearer (my opinion), you could use nested locations:

location /phpmyadmin/ {
    index index.php index.html index.htm;

    location ~ \.php$ {
        fastcgi_pass    127.0.0.1:9000;
        fastcgi_index   index.php;
        fastcgi_param   SCRIPT_FILENAME /usr/share/nginx/html/$uri;
        include     fastcgi_params;
    }
}

You then have to relink phpMyAdmin in your webroot (note the missing alias directive):

unlink /usr/share/nginx/html/phpMyAdmin
ln -s /usr/share/phpMyAdmin /usr/share/nginx/html/phpmyadmin

rewrite ^/phpmyadmin(.*)$ /phpMyAdmin$1;