if (document.images) {

  image1on = new Image();
  image1on.src = "images/about_us_on.gif";

  image2on = new Image();
  image2on.src = "images/volunteer_on.gif";

  image3on = new Image();
  image3on.src = "images/support_on.gif";

  image4on = new Image();
  image4on.src = "images/events_on.gif";

  image5on = new Image();
  image5on.src = "images/resources_on.gif";

  image6on = new Image();
  image6on.src = "images/refer_on.gif";

  image7on = new Image();
  image7on.src = "images/contact_on.gif";

  image8on = new Image();
  image8on.src = "images/home_on.gif";
   
  image9on = new Image();
  image9on.src = "images/programs_on.gif";

  image10on = new Image();
  image10on.src = "images/espanol_on.gif";
       
  image1off = new Image();
  image1off.src = "images/about_us_off.gif";

  image2off = new Image();
  image2off.src = "images/volunteer_off.gif";

  image3off = new Image();
  image3off.src = "images/support_off.gif";

  image4off = new Image();
  image4off.src = "images/events_off.gif";

  image5off = new Image();
  image5off.src = "images/resources_off.gif";

  image6off = new Image();
  image6off.src = "images/refer_off.gif";

  image7off = new Image();
  image7off.src = "images/contact_off.gif";

  image8off = new Image();
  image8off.src = "images/home_off.gif";

  image9off = new Image();
  image9off.src = "images/programs_off.gif";  
  
  image10off = new Image();
  image10off.src = "images/espanol_off.gif";   
  
}

function turnOn(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "on.src");
  }
}

function turnOff(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "off.src");
  }
}
function changeImages() {
  if (document.images) {
    for (var i=0; i<changeImages.arguments.length; i+=2) {
      document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
    }
  }
}