Hi

I have a client that encrypts a message and sends it to the server.  I
can encrypt fine:
            byte[] dataToSend = new byte[somelength];

            /*fill dataToSend with some data*/

            Cipher cipher = Cipher.getInstance("RSA");
        cipher.init(Cipher.ENCRYPT_MODE,  serverPubKey);             byte[]
ciphertext = cipher.doFinal(dataToSend);

However, when I try to decrypt on the server side with:

        Cipher cipher = Cipher.getInstance("RSA");
    cipher.init(Cipher.DECRYPT_MODE,  serverPrivateKey);
    byte[] dataReceived = cipher.doFinal(data);

The output alternates (most of the time is 1 but some times is 2)
between follong errors:

         1.  javax.crypto.BadPaddingException:  Data must start with
zero
         2.  javax.crypto.BadPaddingException:  Message is larger than
modulus.

Does anyone have any idea how I can fix this?