public function setPrefix($prefix)
    {
        // We ensure that the prefix is properly formatted. It
        // must start with a '/' and end without one.
        if($prefix != "") {
            if($prefix[0] != '/') {
                $prefix = '/' . $prefix;
            }
            if($prefix[strlen($prefix) - 1] == '/') {
                $prefix = substr($prefix, 0, strlen($prefix) - 1);
            }
        }

        $this->prefix = $prefix;
        return $this;
    }