<? function sprint_urlencode_and_sign($array, $exp = 60) {
	global $hmac_algo, $secret;
	$exp += time();
	foreach ($array as $key => $value) {
		$send .= urlencode($key).'='.urlencode($value).'&';
	}
	$send .= 'exp='.$exp;
	return '?'.$send.'&sig='.hash_hmac($hmac_algo, $send, $secret);
} ?>