if(document.images) {
 img1on = new Image(); img1on.src = 'img/menue/opt1-2.gif';
 img2on = new Image(); img2on.src = 'img/menue/opt2-2.gif';
 img3on = new Image(); img3on.src = 'img/menue/opt3-2.gif';
 img4on = new Image(); img4on.src = 'img/menue/opt4-2.gif';
 img5on = new Image(); img5on.src = 'img/menue/opt5-2.gif';
 img6on = new Image(); img6on.src = 'img/menue/opt6-2.gif';

 img1off = new Image(); img1off.src = 'img/menue/opt1-1.gif';
 img2off = new Image(); img2off.src = 'img/menue/opt2-1.gif';
 img3off = new Image(); img3off.src = 'img/menue/opt3-1.gif';
 img4off = new Image(); img4off.src = 'img/menue/opt4-1.gif';
 img5off = new Image(); img5off.src = 'img/menue/opt5-1.gif';
 img6off = new Image(); img6off.src = 'img/menue/opt6-1.gif';

 }

function ImgChangeSrc(ImgName, ImgSrc) {
 if(document.images) {
  document[ImgName].src = eval(ImgSrc).src;
  }
 }