Description:
------------
Trying to capture more than 99998 bytes from one string captures nothing. Same behavior happens also in other PCRE functions.

You can see more test results in the original place where was reported: http://tracker.moodle.org/browse/MDL-11237

Reproduce code:
---------------
<?php

/// Change this if you want, but 99999 is the limit in my system (Darwin mbp 8.10.1)
    $numchars = 99999;

/// Test begins here
    echo 'PHP: ' . phpversion() . '<br />';
    echo 'OS: ' . php_uname() . '<br />';
    $all = '';

    for($i=0; $i<$numchars-2; $i++) {
        $all .= 'x';
    }
    $all = '@' . $all . '@';
    preg_match_all('/@(.*?)@/is', $all, $results);
    if ($results[0]) {
        echo 'OK, preg_match_all() has been able to capture one text of ' . strlen($results[0][0]) . ' bytes.<br />';
    } else {
        echo 'ERROR, preg_match_all() has NOT been able to capture one text of ' . strlen($all) . ' bytes.<br />';
    }

?>

Expected result:
----------------
It should show:

OK, preg_match_all() has been able to capture one text of 99999 bytes

Actual result:
--------------
ERROR, preg_match_all() has NOT been able to capture one text of 99999 bytes