waltzie

<?php 
function encrypt_mcrypt($msg, $key, $iv = null) {
	$iv_size = mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC);
	if (!$iv) {
		$iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);
	}
	$pad = $iv_size - (strlen($msg) % $iv_size);
	$msg .= str_repeat(chr($pad), $pad);
	$encryptedMessage = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $key, $msg, MCRYPT_MODE_CBC, $iv);
	return base64_encode($iv . $encryptedMessage);