Capturing process output via OutputDataReceived event

I'm trying to capture process output in "realtime" (while it's running). The code I use is rather simple (see below). For some strange reason the OutputDataReceived event is never called. Why?

private void button2_Click(object sender, EventArgs e)
    {
      // Setup the process start info
      var processStartInfo = new ProcessStartInfo("ping.exe", "-t -n 3 192.168.100.1")
      {
        UseShellExecute = false,
        RedirectStandardOutput = true
      };

      // Setup the process
      mProcess = new Process { StartInfo = processStartInfo, EnableRaisingEvents = true };

      // Register event
      mProcess.OutputDataReceived += OnOutputDataReceived;

      // Start process
      mProcess.Start();
      mProcess.WaitForExit();
    }

    void OnOutputDataReceived(object sender, DataReceivedEventArgs e)
    {
       //Never gets called...
    }