if (document.images) {       
img1on = new Image();           
img1on.src = "images/accueil_button_on.gif"; 
img2on = new Image();
img2on.src = "images/presentation_button_on.gif";  
img3on = new Image();
img3on.src = "images/programmes_button_on.gif";
img4on = new Image();
img4on.src = "images/inscription_button_on.gif";
img5on = new Image();
img5on.src = "images/comment_button_on.gif";  
img6on = new Image();
img6on.src = "images/articles_button_on.gif";  
img7on = new Image();
img7on.src = "images/telechargements_button_on.gif"; 

en_img1on = new Image();           
en_img1on.src = "images/en_home_button_on.gif"; 
en_img2on = new Image();
en_img2on.src = "images/en_introduction_button_on.gif";  
en_img3on = new Image();
en_img3on.src = "images/en_programs_button_on.gif";
en_img4on = new Image();
en_img4on.src = "images/en_registration_button_on.gif";
en_img5on = new Image();
en_img5on.src = "images/en_how_button_on.gif";  
en_img6on = new Image();
en_img6on.src = "images/en_articles_button_on.gif";  
en_img7on = new Image();
en_img7on.src = "images/en_downloads_button_on.gif";  

img1off = new Image();           
img1off.src = "images/accueil_button_off.gif"; 
img2off = new Image();
img2off.src = "images/presentation_button_off.gif";  
img3off = new Image();
img3off.src = "images/programmes_button_off.gif";
img4off = new Image();
img4off.src = "images/inscription_button_off.gif";
img5off = new Image();
img5off.src = "images/comment_button_off.gif";  
img6off = new Image();
img6off.src = "images/articles_button_off.gif";  
img7off = new Image();
img7off.src = "images/telechargements_button_off.gif";  

en_img1off = new Image();           
en_img1off.src = "images/en_home_button_off.gif"; 
en_img2off = new Image();
en_img2off.src = "images/en_introduction_button_off.gif";  
en_img3off = new Image();
en_img3off.src = "images/en_programs_button_off.gif";
en_img4off = new Image();
en_img4off.src = "images/en_registration_button_off.gif";
en_img5off = new Image();
en_img5off.src = "images/en_how_button_off.gif";  
en_img6off = new Image();
en_img6off.src = "images/en_articles_button_off.gif";  
en_img7off = new Image();
en_img7off.src = "images/en_downloads_button_off.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");        }}

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