I have attached the Java program that will reproduce the bug. The program tries to convert the unicode byte array in Big5 encoding to a String and then get the bytes back by doing String.getBytes("Big5").

The bytes returned form the String.getBytes() method should return the
original bytes. The program tries to convert the following Big5 characters
f9d4
f9d5
f9d6
f9d7
f9d8
f9dd
f9de

but only the first two are converted back correctly (i.e f9d4 and f9d5) and
the others fail to convert correctly.

The bug is failing for customer using JDK 1.3
However, I can reproduce the problem using both JDK's:
ladybird JDK 1.3.1-rc1-b19 and merlin JDK 1.4.0-beta-b56.

Here's the test case:

public class f2 {
    
    public static String hexStr(byte b) {
        int i= 0xff & b;
        return "0x" + Integer.toString(i, 16);
    }

    public static void main(String arg[]) {

    try {
        byte inbuf[][] =  {
            { (byte)0xf9, (byte)0xd4 },
            { (byte)0xf9, (byte)0xd5 },
            { (byte)0xf9, (byte)0xd6 },
            { (byte)0xf9, (byte)0xd7 },
            { (byte)0xf9, (byte)0xd8 },
            { (byte)0xf9, (byte)0xdd },
            { (byte)0xf9, (byte)0xde },
        };

        System.out.println("platform encoding = " +
                            System.getProperty("file.encoding"));

        for (int i=0;i<inbuf.length;i++) {
            System.out.println("Original bytes :" + 
                               hexStr(inbuf[i][0])+" "+hexStr(inbuf[i][1]));

            String s = new String(inbuf[i], "BIG5");
            byte buf[] = s.getBytes("BIG5");
            System.out.print("Converted bytes:" );
            for (int b=0;b<buf.length;b++) {
               System.out.print(hexStr(buf[b])+" ");
            }
            System.out.println("");

        }

        } catch (java.io.UnsupportedEncodingException e) {
        System.out.println("ERROR: "+ e);
        }
    }
}

Here's the output:

platform encoding = BIG5
Original bytes :0xf9 0xd4
Converted bytes:0xf9 0xd4 
Original bytes :0xf9 0xd5
Converted bytes:0xf9 0xd5 
Original bytes :0xf9 0xd6
Converted bytes:0x3f 
Original bytes :0xf9 0xd7
Converted bytes:0x3f 
Original bytes :0xf9 0xd8
Converted bytes:0x3f 
Original bytes :0xf9 0xdd
Converted bytes:0x3f 
Original bytes :0xf9 0xde
Converted bytes:0x3f