Description:
------------
Some zip files can't be opened by php_zip while they can be open by normal zip utility like haozip, 7-z, winrar, eg.

Test script:
---------------
<?php

$a1 = 'a1.zip';
$a2 = 'a2.zip';

$zip = @zip_open($a2);
if (is_resource($zip)) {
    echo 'pass a2';
} else {
    echo 'error a2 ' . $zip;
}

    echo '<br />';

$zip = @zip_open($a1);
if (is_resource($zip)) {
    echo 'pass a1';
} else {
    echo 'error a1 ' . $zip;
}

?>

a1.zip can be downloaded from http://afeng.open-src.com/a1.zip
a2.zip can be downloaded from http://afeng.open-src.com/a2.zip

Expected result:
----------------
pass a2
pass a1

Actual result:
--------------
error a2 19
pass a1