WiFiUDP.remoteIp() hangs up....

Hi there,

I have a problem what is driving me crazy and i can't find any help by searching the internet and this forum for similar troubles.

I have started to write a sketch (most stuff out from tutorials) to receive and send UDP packets to/from my Arduino Due with WiFiShield. The idea is to receive commands from a java-app and perform some actions after receiving a command.

The sketch-code where the problem appears:

void loop() {
  // check if UDP Packet is available
  int packetSize = Udp.parsePacket();
    Serial.print("INF: Received packet of size ");
    Serial.print("INF: From ");
    IPAddress remoteIp = Udp.remoteIP();
    // read packet into packetBuffer
    int len = Udp.read(packetBuffer, 255);
    if(len > 0) packetBuffer[len] = 0;

    // send reply back
    Udp.beginPacket(Udp.remoteIP(), Udp.remotePort());

here is the output of my serial:

INF: serial connection initialized (9600)
INF: WiFi Shield found
INF: trying to connect to WPA SSID 'DiZZyNet'...
INF: connected to WiFi network 'DiZZyNet'
IP Address:
MAC address: 78:C4:E:2:C:6A
INF: started UDP on Port 2390
INF: Received packet of size 2
INF: From

This is where I get struggled. It seems that Udp.parsePacket(); receives a packet of size 2, but cannot resolve the remoteIP.