if (document.images)
{
   var home_off = new Image(); home_off.src = "images/home_off.gif";
   var home_on = new Image(); home_on.src = "images/home_on.gif";
  
   var store_off = new Image(); store_off.src = "images/store_off.gif";
   var store_on = new Image(); store_on.src = "images/store_on.gif";
  
   var about_off = new Image(); about_off.src = "images/about_off.gif";
   var about_on = new Image(); about_on.src = "images/about_on.gif";
  
   var contact_off = new Image(); contact_off.src = "images/contact_off.gif";
   var contact_on = new Image(); contact_on.src = "images/contact_on.gif";
  
   var links_off = new Image(); links_off.src = "images/links_off.gif";
   var links_on = new Image(); links_on.src = "images/links_on.gif";
  
   var jobs_off = new Image(); jobs_off.src = "images/jobs_off.gif";
   var jobs_on = new Image(); jobs_on.src = "images/jobs_on.gif";


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


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