If you wish a version of parse_str sans magic quotes, the following will do the trick:

<?php
function parse_query($str) {
    $pairs = explode('&', $str);

    foreach($pairs as $pair) {
        list($name, $value) = explode('=', $pair, 2);
        global $$name;
        $$name = $value;
    }
}
?>