[PHP] $_POST was empty due to syntax error

So last night I thought I'd install PHP5.2 on my WAMP server at home. Big mistake. 4 hours later I've wiped my server and reinstalled from WAMPServer2.0. Everything appears to be ok except my main login form wouldn't post or get data:

<?php
error_reporting(E_ALL);

echo "<pre>";
$data = file_get_contents('php://input');
var_dump($data);
print_r($_REQUEST);
print_r($_POST);
print_r( $GLOBALS );
print_r( $HTTP_GET_VARS );
print_r( $HTTP_POST_VARS );
echo "</pre>";
?>

When I ran this and posted the form I'd get:

string(0) ""
Array()
Array()
Array
(
[GLOBALS] => Array
*RECURSION*
[_POST] => Array
(
)

[_GET] => Array
(
)

[_COOKIE] => Array
(
[logged_in] => 1
[PHPSESSID] => lrl9o34cc5p3u3fmd1dl502s51
)

[_FILES] => Array
(
)

[_REQUEST] => Array
(
)

[error] =>
[lemail] =>
[lpass] =>
[lrem] => 0
[data] =>
)

Notice: Undefined variable: HTTP_GET_VARS in C:\wamp\www\eazine\ver2\login.php on line 15

Notice: Undefined variable: HTTP_POST_VARS in C:\wamp\www\eazine\ver2\login.php on line 16

Reducing the form and checking all syntax, I found that the form itself was in a showform() function which took in 2 parameters, but on the initial call, I only had one, showform(""). Changing it to showform("", "") resolved the issue.

Any reason why a) the form would still show and error_reporting wouldn't catch it? b) the resulting post would be empty? It had me googling for about a hour and a half before I figured it out.