Description:
------------
If the 3rd registerfunction (for messageboxa) is commented out, the code works properly.

Tested with cli version of php.

Reproduce code:
---------------
<?php
error_reporting(E_ALL);

$api = new win32();

$api->registerfunction("long GetTickCount () From Kernel32.dll");
echo "Ticks=",$api->GetTickCount(),"\n";

$api->registerfunction("long GetUserName (string &a, int &b) From advapi32.dll");
$s1 = "                                        ";
$size = strlen($s1);

$api->GetUsername($s1,$size);
$s1 = substr($s1,0,$size);
echo "u='$s1'\n";

print_r(get_class_methods($api));
$api->registerfunction("int MessageBoxA(long hWnd, string &title, string &lpCaption, int uType) from User32.dll");
?>

Expected result:
----------------
Ticks=192755858
u='jlim '
Array
(
    [0] => registerfunction
    [1] => unregisterfunction
    [2] => registercallback
    [3] => definetype
    [4] => gettypesize
    [5] => inittype
    [6] => decref
    [7] => gettickcount
    [8] => getusername
)
<br />

Actual result:
--------------
Ticks=192755858
u='jlim '
Array
(
    [0] => registerfunction
    [1] => unregisterfunction
    [2] => registercallback
    [3] => definetype
    [4] => gettypesize
    [5] => inittype
    [6] => decref
    [7] => gettickcount
    [8] => getusername
)
<br />
<b>Fatal error</b>:  Call to undefined function:  registerfunction() in <b>d:\in
etpub\wwwroot\php\w32.inc.php</b> on line <b>18</b><br />