Way to pass all HTTP requests headers verbatim to PHP-FastCGI server?

[Alex]

Hi,

I would require to access via PHP a client's unmodified HTTP request
headers. Using standard PHP variables ($_SERVER etc.) isn't an option
since these store headers in normalized form; but I would need to have
them verbatim, so for instance, "Keep-Alive" versus "keep-alive"
matters. 

Running PHP with Apache (whether as CGI or as a module) would allow you
to access the headers via the apache_request_headers() PHP function. 

Do you know of a way how I could pass request headers from Nginx to PHP
without having them modified?

Thanks in advance.

Alex