Java Card

Hello,

I have a BIG problem with
PCSC Exception in method SCardTransmit: error occurred with SCardTransmit
return code = 8010002f

Moreover, in my applet, I have a method that generates 4 bytes (I have test it with more) of RandomData in the following way:

...
private RandomData random;
...
...
private void printRandom(APDU apdu) throws ISOException, CryptoException {
byte[] apduBuffer = apdu.getBuffer();
apdu.setIncomingAndReceive();

if (apduBuffer[4] != 0)
throw new ISOException(ISO7816.SW_WRONG_LENGTH);

byte[] randomBuffer = new byte[4];
this.random = RandomData.getInstance(RandomData.ALG_SECURE_RANDOM);
this.random.generateData(randomBuffer, (short) 0, (short) 4);
apduBuffer[5] = (byte) (randomBuffer[0]);
apduBuffer[6] = (byte) (randomBuffer[1]);
apduBuffer[7] = (byte) (randomBuffer[2]);
apduBuffer[8] = (byte) (randomBuffer[3]);
apdu.setOutgoingAndSend((short) 5, (short) 4);
}
...

I am using Java Card 2.2.1, GemXpresso RAD 3 with Open Card and Eclipse IDE.

When I test this applet on the GemXpresso Simulator, I have no problems, everything is going smoothly, and I receive the expected output. However, when I install the applet on the smart card (GemXpresso 211 PK), and I run the applet from a host application (Eclipse) I receive this error. Strangely enough, it works when I generate 2 bytes, and sometimes works when I generate 4 bytes, but NOT more.
WHY ? Can anybody help? I am trying to understand and solve this problem...

I looked at some OCF forums, and all I could find was:
1) to use the APDU.waitExtension()
2) busy loop
Maybe I do something wrong, because both of these solutions do not work for me.

Any ideas, suggestions, remarks, would be highly appreciated.

Best Regards,
Bojan