private static BigInteger[] convertASN1toBIGINT(byte derbytes[])
throws IOException {
ByteArrayInputStream bIn = new ByteArrayInputStream(derbytes);
DERInputStream dIn = new DERInputStream(bIn);
DERConstructedSequence seq = (DERConstructedSequence) dIn.readObject();
BigInteger r = ((DERInteger) seq.getObjectAt(0)).getValue();
BigInteger s = ((DERInteger) seq.getObjectAt(1)).getValue();
BigInteger result[] = new BigInteger[2];
result[0] = r;