UdpSocket on Applet receives only 1 byte in vm 1.3.1_15. All works on 1.4.2

Question

Friends I am having a problem that might be easy to solve but I don't seem to find the solution:
I made an applet that listens udp xml transmissions, very basic, nothing fancy. I made it with jdk 1.4.2 it allways worked fine. Yesterday I tried to make it work on clients with JRE 1.3.1 on their machines, so I compiled a new version of the same applet with the jdk 1.3.1_15 and it worked perfectly. But when I tested it on a client that had only the JRE 1.3.1_15 I found out that the applet, o better yet, the UdpSocket receives only one single byte. Actually de '<' char from the begining of xml.
This is the code that listens and the same code works fine with VM 1.4.2:
BEFORE IS THE INITIALIZATION CODE FOR THE SOCKET:
private static final int DEFAULT_BUFFER=32768;
DatagramPacket packet=new DatagramPacket(buf, buf.length);
packet.setLength(this.DEFAULT_BUFFER);
this.mSocket=new DatagramSocket(this.mPort, localAddress);
this.mSocket.setReceiveBufferSize(this.DEFAULT_BUFFER);NOW THE LISTENING CODE:
if(this.mDebug)
  System.out.println("Buffer["+this.mSocket.getReceiveBufferSize()+"].");
//Receive data
this.mSocket.receive(packet);
byte[] data=new byte[packet.getLength()];
//output debug info
if(this.mDebug)
System.out.println("Packet [len="+ packet.getLength() +"].");
//copy data into a new array
System.arraycopy(packet.getData(), 0, data, 0, data.length);
//notify data arrival
this.notifyDataArrival(data);SUMMARY:
Originally built on vm 1.4.2 the applet now compiled on 1.3.1 jdk, only works fine in vm's 1.4.2 and not in the 1.3.1 where it only receives a single byte per mSocket.receive(packet) call.
Please helpme out.
Thanks in advance,
Frank

Answer 1

(a) Set the packet length to the actual length of the array, and no longer.
(b) Reset it to this length before every receive, otherwise the DatagramPacket will shrink to the size of the smallest datagram received so far.