// From http://code.calum.org/
		public static byte[] decryptSymmetric(byte[] cryptWhole, PrivateKey privKey){
    //    System.out.println("decryptSymmetric: cryptWhole is " + cryptWhole.length + " bytes");
        // get the first 256 bytes
        byte[] cryptKey = new byte[256];
        System.arraycopy(cryptWhole, 0, cryptKey, 0, 256);
        //System.out.println("Copied into cryptKey");

        // decrypt
        byte[] skeyBytes = decrypt(cryptKey, privKey);
        // If we're here, we've successfully decrypted the secret key.
        //System.out.println("Decrypted the secret key");

        // get the rest of the packet
        int cryptDataSize   = cryptWhole.length - 256;
    //    System.out.println("decryptSymmetric: cryptDataSize is " + cryptDataSize + " bytes");
        byte[] cryptData    = new byte[cryptDataSize];
        System.arraycopy(cryptWhole, 256, cryptData, 0, cryptDataSize);
        //System.out.println("Got cryptData as " + cryptData);

        byte[] decrypted    = null;

        try {
            // decrypt data with random key
            KeyGenerator kgen = KeyGenerator.getInstance(Main.SYMMETRIC);
            kgen.init(Main.SYMMETRICBITS);

            SecretKeySpec skeySpec = new SecretKeySpec(skeyBytes, Main.SYMMETRIC);
            Cipher cipher = Cipher.getInstance(Main.SYMMETRIC);
            cipher.init(Cipher.DECRYPT_MODE, skeySpec);

            byte[] decryptedZipped = cipher.doFinal(cryptData);
     //       System.out.println("decryptSymmetric: decrypted size is " + decrypted.length + " bytes");
            decrypted       = Functions.decompressByteArray(decryptedZipped);
            return decrypted;
        } catch (InvalidKeyException ex) {
            System.err.println(ex.toString());
            System.err.println("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!\n" +
                    "! If you see this, you've got some problems with your crypto stuff\n" +
                    "! You probably need to install the JCE extensions for strong crypto.\n" +
                    "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");
        } catch (NoSuchPaddingException ex) {
            System.err.println(ex.toString());
        } catch (NoSuchAlgorithmException ex) {
            System.err.println(ex.toString());
        } catch (IllegalBlockSizeException ex) {
            System.err.println(ex.toString());
        } catch (BadPaddingException ex) {
            System.err.println(ex.toString());
        }

        return null;
    }
}