private static byte[] get4bytes(long l)
	{
		// break down to bytes
		byte a[] = new byte[4];
		a[0] = (byte)(l >> 24);
		a[1] = (byte)(l >> 16);
		a[2] = (byte)(l >> 8);
		a[3] = (byte)(l >> 0);
		// assemble back
		// ll != l.
		long ll = (unsigned(a[0]) << 24) | (unsigned(a[1]) << 16) | (unsigned(a[2]) <<8) | unsigned(a[3]);
		System.err.println("original " + l);
		System.err.println("new      " + ll);
                // output:
                // original 33996344
                // new      33963576


		return a;
	}
	
	static byte unsigned(byte b)
	{
		if (b < 0)
		{
			b += 128;
		}
		return b;
	}