A POST should also work, until you explicitly banned it (like they did for the Gamestudio manual).

Here is the output from one of my server scripts:
Code:
HTTP/1.1 200 OK
Date: Fri, 05 Nov 2010 08:29:04 GMT
Server: Apache
Vary: Accept-Encoding
Connection: close
Transfer-Encoding: Identity
Content-Type: text/html

66308

(HTTP GET)

Code:
HTTP/1.1 200 OK
Date: Fri, 05 Nov 2010 08:27:13 GMT
Server: Apache
Vary: Accept-Encoding
Connection: close
Transfer-Encoding: Identity
Content-Type: text/html

66308

(HTTP POST)


As you can see, only the time in the header differs a bit, but I'm pretty sure that the http_sendPost() function already cropped this out of the answer.

However, like I already mentioned, there are scripts that don't allow HTTP POST, like the manual.
I got this response from http://www.conitec.net/beta/http.htm
Code:
HTTP/1.1 405 Method Not Allowed
Date: Fri, 05 Nov 2010 08:30:42 GMT
Server: Apache
Allow: GET, HEAD, OPTIONS
Connection: close
Transfer-Encoding: Identity
Content-Type: text/html; charset=iso-8859-1

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML><HEAD>
<TITLE>405 Method Not Allowed</TITLE>
</HEAD><BODY>
<H1>Method Not Allowed</H1>
The requested method POST is not allowed for the URL /beta/http.htm.<P>
</BODY></HTML>


Shitlord by trade and passion. Graphics programmer at Laminar Research.
I write blog posts at feresignum.com