Nginx - Rewrites help.

Hello,

I have been scratching my head last 2 days trying to get this working:

I have a Rails application, say, http://example.com and now I want to run a PHP app on http://example.com/coupons

I set up the PHP app but I am having a hard time with nginx rewrites. I hope someone here can assist me:

Here's how I set up things in nginx.conf

     location /coupons/ {
          alias /home/jjobanputra/code/coupon/upload/;
          index index.php index.html index.htm;
          if (-e $request_filename) {
            expires 30d;
            break;
          }
          rewrite /coupons/(.+)$ /coupons/index.php?q=$1;
        }

        location = /coupons {
          try_files $uri $uri/ @coupons;
        }

        location @coupons {
          include         fastcgi_params;
          fastcgi_pass 127.0.0.1:53217;
          fastcgi_split_path_info ^(/coupons)(/.*)$;
          fastcgi_param SCRIPT_FILENAME /home/jjobanputra/code/coupon/upload/index.php;
          fastcgi_param PATH_INFO $fastcgi_path_info;
        }

        location ~ /coupons/?.*\.php$ {
          if ($fastcgi_script_name ~ /coupons/?(.*)$) {
            set $valid_fastcgi_script_name /$1;
          }
          fastcgi_pass 127.0.0.1:53217;
          fastcgi_index index.php;
          fastcgi_param SCRIPT_FILENAME /home/jjobanputra/code/coupon/upload/$valid_fastcgi_script_name;
          include /opt/nginx/conf/fastcgi.conf;
        }

Now http://example.com/coupons loads up the home page, however if I try http://example.com/coupons/ (with the extra slash), it says "No input file found"

Same goes with http://example.com/coupons/Admin and so on.. somehow the rewrites are screwed up i guess..

PS: The above code has been tweaked again and again, so if there is something silly, be nice and let me know ;)