Hello,

OpenBSD grey.my.domain 5.5 GENERIC.MP
# mono --version
Mono JIT compiler version 2.10.9
# nginx -V
nginx version: nginx/1.4.4

i have exactly the same problem, i run the aspx with a very explicit path:

# fastcgi-mono-server4 /applications=grey:/index.aspx:./moon/index.aspx /socket=tcp:127.0.0.1:9000 /loglevels=Debug /verbose=True /root=/var/www/

I use this nginx http conf :
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
server {
server_name grey;
root /var/www/moon/;
index index.html index.htm index.aspx default.aspx;

location = /favicon.ico {
log_not_found off;
access_log off;
}

location = /robots.txt {
allow all;
log_not_found off;
access_log off;
}

location / {
fastcgi_index index.aspx;
fastcgi_pass 127.0.0.1:9000;
include fastcgi_params;
fastcgi_param PATH_INFO "";
fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
#try_files $uri $uri/ /index.aspx;
}

# Fighting with ImageCache? This little gem is amazing.
location ~ ^/sites/.*/files/imagecache/ {
try_files $uri $uri/ @rewrite;
}
}
-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Then i copied-pasta the MVC application, expecting the /bin to be detected etc...

# fastcgi-mono-server4 /applications=grey:/:./moon/MonoWeb /socket=tcp:127.0.0.1:9000 /loglevels=Debug /verbose=True /root=/var/www/

i also ran as root and using tcp socket to just test the xsp.

The fastcgi-mono-server4 just say nothing , nor reply the request.

Best regards.