@shizobuddy: /path/to/php is usually $document_root if set properly so you come up with the following generic config:

fastcgi_param SCRIPT_FILENAME $document_root/$fastcgi_script_name;

@androo: instead of setting fastcgi_param in a if (in fact you can't), you can still set variables to do so. Example

[code]
set $script index.php;
set $path_info "";
if ($uri ~ "^(.+\.php)(.*)") {
set $script $1;
set $path_info $2;
}
fastcgi_param PATH_INFO $path_info;
....
[/code]