function showImg(imgNumber,rel_val,className){
	var i;
	var elName;
	var linkName;
	var imgFrame;
	var imgLink;
	
	for(i=1;i<=4;i++){               		
    elName=rel_val+"_"+i;	
    linkName='link_'+rel_val+"_"+i;
    
   imgFrame=document.getElementById (elName);
   imgLink=document.getElementById (linkName);
   
    if(imgFrame){
      imgFrame.className='hidden';
      if(imgLink)
        imgLink.className='';

      if (i==imgNumber){
        imgFrame.className= className;
        if(imgLink)
          imgLink.className='on';
      }

    }
  }         
}