if (document.images) {

news_on = new Image();  
news_on.src = "images/hu/news_on.gif";  
news_off = new Image();
news_off.src = "images/hu/news_off.gif";
aboutus_on = new Image();  
aboutus_on.src = "images/hu/aboutus_on.gif";  
aboutus_off = new Image();
aboutus_off.src = "images/hu/aboutus_off.gif";
competitions_on = new Image();  
competitions_on.src = "images/hu/competitions_on.gif";  
competitions_off = new Image();
competitions_off.src = "images/hu/competitions_off.gif";
gallery_on = new Image();  
gallery_on.src = "images/hu/gallery_on.gif";  
gallery_off = new Image();
gallery_off.src = "images/hu/gallery_off.gif";
links_on = new Image();  
links_on.src = "images/hu/links_on.gif";  
links_off = new Image();
links_off.src = "images/hu/links_off.gif";
contactus_on = new Image();  
contactus_on.src = "images/hu/contactus_on.gif";  
contactus_off = new Image();
contactus_off.src = "images/hu/contactus_off.gif";
zt_on = new Image();  
zt_on.src = "images/hu/zt_on.gif";  
zt_off = new Image();
zt_off.src = "images/hu/zt_off.gif";
ztf_on = new Image();  
ztf_on.src = "images/hu/ztf_on.gif";  
ztf_off = new Image();
ztf_off.src = "images/hu/ztf_off.gif";
other_on = new Image();  
other_on.src = "images/hu/other_on.gif";  
other_off = new Image();
other_off.src = "images/hu/other_off.gif";
archives_on = new Image();  
archives_on.src = "images/hu/archives_on.gif";  
archives_off = new Image();
archives_off.src = "images/hu/archives_off.gif";
}

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

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