// From http://code.calum.org/
		public static byte[] encrypt(byte[] plain, PublicKey pk) {
        Logger log = Logger.getLogger("foo");
        try {
            Cipher cipher = Cipher.getInstance(Main.ASYMMETRIC);
            cipher.init(Cipher.ENCRYPT_MODE, pk);
            return cipher.doFinal(plain);
        } catch (InvalidKeyException ex) {
            System.err.println(ex.toString());
        } catch (NoSuchAlgorithmException ex) {
            System.err.println(ex.toString());
        } catch (IllegalBlockSizeException ex) {
            System.err.println(ex.toString());
        } catch (NoSuchPaddingException ex) {
            System.err.println(ex.toString());
        } catch (BadPaddingException ex) {
            System.err.println(ex.toString());
        }
        return null;
    }