// main Nav

if (document.images) {
  homeon=new Image();
  homeon.src="../images/home_over.gif";
  homeoff=new Image();
  homeoff.src="../images/home.gif";

  abouton=new Image();
  abouton.src="../images/about_over.gif";
  aboutoff=new Image();
  aboutoff.src="../images/about.gif";
 
  contacton=new Image();
  contacton.src="../images/contact_over.gif";
  contactoff=new Image();
  contactoff.src="../images/contact.gif";
  
  tidiffon=new Image();
  tidiffon.src="../images/tidifference_over.gif";
  tidiffoff=new Image();
  tidiffoff.src="../images/tidifference.gif";
  
  drugdevon=new Image();
  drugdevon.src="../images/drugdev_over.gif";
  drugdevoff=new Image();
  drugdevoff.src="../images/drugdev.gif";
  
  techasson=new Image();
  techasson.src="../images/techass_over.gif";
  techassoff=new Image();
  techassoff.src="../images/techass.gif";
  
  newson=new Image();
  newson.src="../images/newspub_over.gif";
  newsoff=new Image();
  newsoff.src="../images/newspub.gif";
  

}



  function imgOn(imgName) {
  if (document.images) {
     document[imgName].src=eval(imgName + "on.src");
      }
  }
  function imgOff(imgName) {
  if (document.images) {
      document[imgName].src=eval(imgName + "off.src");
      }
  }



// preload main Nav images


var preloadFlag = false;

function preloadImages() {

     if (document.images) {

		homeon = newImage("../images/home_over.gif");
		
		abouton = newImage("../images/about_over.gif");
		
		contacton = newImage("../images/contact_over.gif");
		
		tidiffon = newImage("../images/tidifference_over.gif");
		
		drugdevon = newImage("../images/drugdev_over.gif");
		
		techasson = newImage("../images/techass_over.gif");
		
		newson = newImage("../images/newspub_over.gif");

		preloadFlag = true;
		
	}
	
}