menu1=new menu("imgmain/menu1.jpg","imgmain/menu1-over.jpg");
 menu2=new menu("imgmain/menu2.jpg","imgmain/menu2-over.jpg");
 menu3=new menu("imgmain/menu3.jpg","imgmain/menu3-over.jpg");

 function menu(norm_src,sel_src)
 {
  this.norm=new Image();
   this.sel=new Image();
  this.norm.src=norm_src;
   this.sel.src=sel_src; 
 }

 function on(ImageName)
 {
   NewSrc11=eval(ImageName+".sel.src");
   document[ImageName].src=NewSrc11;   
 }

 function off(ImageName)
 {
   NewSrc21=eval(ImageName+".norm.src");
   document[ImageName].src=NewSrc21;  
 }