Description:
------------
On a Linux Apache server (1.3.31), PHP loses request variables when they were sent using the POST method and the script is protected via .htaccess authentication 
(bug produced with user & password authentication).
The form data are nowhere to be found, not in $_REQUEST or $_POST.

My $_SERVER is as follows:

(
    [CONTENT_LENGTH] => 21
    [CONTENT_TYPE] => application/x-www-form-urlencoded
    [DOCUMENT_ROOT] => /home/www/<host name>/htdocs
    [HTTP________] => ----:-------------------------------
    [HTTP________________] => ----- -------
    [HTTP_ACCEPT] => image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, application/x-shockwave-flash, */*
    [HTTP_ACCEPT_LANGUAGE] => de
    [HTTP_CACHE_CONTROL] => no-cache
    [HTTP_CONNECTION] => Keep-Alive
    [HTTP_HOST] => <host name>
    [HTTP_USER_AGENT] => Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; iOpus-I-M)
    [PATH] => /sbin:/bin:/usr/sbin:/usr/bin
    [REMOTE_ADDR] => 217.236.36.198
    [REMOTE_PORT] => 2029
    [SCRIPT_FILENAME] => /home/www/<host name>/htdocs/v1/phpbug/test.php
    [SCRIPT_URI] => http://<host name>/v1/phpbug/test.php
    [SCRIPT_URL] => /v1/phpbug/test.php
    [SERVER_ADDR] => 81.3.18.152
    [SERVER_ADMIN] => <removed>
    [SERVER_NAME] => <host name>
    [SERVER_PORT] => 80
    [SERVER_SIGNATURE] => 
    [SERVER_SOFTWARE] => Apache/1.3.31 (Unix) mod_ssl/2.8.19 OpenSSL/0.9.7d PHP/4.3.8
    [UNIQUE_ID] => QU7XaH8AAAEAAASeDko
    [GATEWAY_INTERFACE] => CGI/1.1
    [SERVER_PROTOCOL] => HTTP/1.1
    [REQUEST_METHOD] => POST
    [QUERY_STRING] => 
    [REQUEST_URI] => /v1/phpbug/test.php
    [SCRIPT_NAME] => /v1/phpbug/test.php
    [PATH_TRANSLATED] => /home/www/<host name>/htdocs/v1/phpbug/test.php
    [PHP_SELF] => /v1/phpbug/test.php
)


Reproduce code:
---------------
-- html input form
<form action="phpbug/test.php" method=post>
POST <input type=text name="a"> <input type=submit>
<hr>
<form action=phpbug/test.php" method=get>
GET <input type=text name="a"> <input type=submit>

--php script
<?php
echo "<pre>";
print_r($_POST);
echo "--";
print_r($_REQUEST);
echo "--";
print_r($_SERVER);
?>


Expected result:
----------------
Array
(
    [a] => dfdsfds
)
--Array
(
    [a] => dfdsfds
)

[as obtained when using the GET method]

Actual result:
--------------
Array
(
    [a] => 
)
--Array
(
    [a] => 
)

NOTE: the $_SERVER[CONTENT_LENGTH] is correct.