if (document.images) {
  tl0off= new Image(230,130); 
  tl0off.src="images/tlacitka/nabor1.jpg"; 
  tl0on= new Image(230,130); 
  tl0on.src="images/tlacitka/nabor2.jpg"; 

  tl1off= new Image(230,130); 
  tl1off.src="images/tlacitka/zajezdy1.jpg"; 
  tl1on= new Image(230,130); 
  tl1on.src="images/tlacitka/zajezdy2.jpg"; 

  tl2off= new Image(230,130); 
  tl2off.src="images/tlacitka/sport1.jpg"; 
  tl2on= new Image(230,130); 
  tl2on.src="images/tlacitka/sport2.jpg"; 
  
  tl3off= new Image(230,130); 
  tl3off.src="images/tlacitka/klubovna1.jpg";
  tl3on= new Image(230,130); 
  tl3on.src="images/tlacitka/klubovna2.jpg"; 
  
  tl4off= new Image(230,130); 
  tl4off.src="images/tlacitka/marketing1.jpg";
  tl4on= new Image(230,130); 
  tl4on.src="images/tlacitka/marketing2.jpg"; 
}

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

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