if (document.images) {
  homenorm = new Image();
  homenorm.src = "images/tbHome.gif";
  homeover = new Image();
  homeover.src = "images/tbHome-over.gif";
  newsnorm = new Image();
  newsnorm.src = "images/tbNews.gif";
  newsover = new Image();
  newsover.src = "images/tbNews-over.gif";
  aboutnorm = new Image();
  aboutnorm.src = "images/tbAbout.gif";
  aboutover = new Image();
  aboutover.src = "images/tbAbout-over.gif";
  faqnorm = new Image();
  faqnorm.src = "images/tbFAQ.gif";
  faqover = new Image();
  faqover.src = "images/tbFAQ-over.gif";
}

function normImg(imgName) {
  if (document.images) {
    document.images[imgName].src = eval(imgName + "norm.src");
  }
}

function overImg(imgName) {
  if (document.images) {
    document.images[imgName].src = eval(imgName + "over.src");
  }
}