if (document.images) {
  contactButtonOff = new Image();
  contactButtonOff.src = "images/contactButtonOff.gif";
  contactButtonOn = new Image();
  contactButtonOn.src = "images/contactButtonOn.gif";
  
  homeButtonOff = new Image();
  homeButtonOff.src = "images/homeButtonOff.gif";
  homeButtonOn = new Image();
  homeButtonOn.src = "images/homeButtonOn.gif";
  
  designButtonOff = new Image();
  designButtonOff.src = "images/designButtonOff.gif";
  designButtonOn = new Image();
  designButtonOn.src = "images/designButtonOn.gif";
  
  personnelButtonOff = new Image();
  personnelButtonOff.src = "images/personnelButtonOff.gif";
  personnelButtonOn = new Image();
  personnelButtonOn.src = "images/personnelButtonOn.gif";
  
  companyHistoryButtonOff = new Image();
  companyHistoryButtonOff.src = "images/companyHistoryButtonOff.gif";
  companyHistoryButtonOn = new Image();
  companyHistoryButtonOn.src = "images/companyHistoryButtonOn.gif";
  
  remodelsButtonOff = new Image();
  remodelsButtonOff.src = "images/remodelsButtonOff.gif";
  remodelsButtonOn = new Image();
  remodelsButtonOn.src = "images/remodelsButtonOn.gif";
  
  customHomesButtonOff = new Image();
  customHomesButtonOff.src = "images/customHomesButtonOff.gif";
  customHomesButtonOn = new Image();
  customHomesButtonOn.src = "images/customHomesButtonOn.gif";
  
  currentEventsButtonOff = new Image();
  currentEventsButtonOff.src = "images/currentEventsButtonOff.gif";
  currentEventsButtonOn = new Image();
  currentEventsButtonOn.src = "images/currentEventsButtonOn.gif";
}

function imageOn(buttonName) {
  if (document.images) {
    document.getElementById(buttonName).src = eval(buttonName + "On.src");
  }
}

function imageOff(buttonName) {
  if (document.images) {
    document.getElementById(buttonName).src = eval(buttonName + "Off.src");
  }
}

function isValidEmail(email) {
  if (/^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/.test(email))
    return true;
  else {
    alert("You must enter a valid email address.");
    return false;
  }
}