Why do I get an error  saying : VDIG not installed correct.when I am trying to capture from an an external video camera connected via firewire on a mac? What does it mean?

I am trying to take footage from 2 cameras:
cam1 camera built in the mac
cam2 an external connected via firewire

I am using QuickTime 7 and Processing 1.5.1
My operating system,: Mac ox 10.6.8
This is the code I am trying to use I found from another user. Do I need to change the code to work on Mac?
I am new to Processing and any help will be appreciated.

import processing.video.*;

Capture cam1;
Capture cam2;
int currX, currY;
int capWidth, capHeight;
boolean isCapturing;

PFont font;

void setup() {

  size(640, 240);

  String[] devices = Capture.list();
  println(devices);

  currX = 0;
  currY = 0;
  capWidth = 320;
  capHeight = 240;

  cam1 = new Capture(this, 320, 240, devices[0]);
  cam2 = new Capture(this, 320, 240, devices[1]);
  isCapturing = true;
}

void draw() {

  image(cam1, currX, currY);
  image(cam2, 320, currY);
}

void captureEvent(Capture c) {
  c.read();
}

void keyPressed() {
  if (key == ' ') {

    isCapturing = !isCapturing;
    saveFrame("####.jpg");
  }
}