function isInt (str)
{
  var i = parseInt (str);

  if (isNaN (i))
    return false;

  i = i . toString ();
  if (i != str)
    return false;

  if (i <= 0)
    return false;

  return true;
}

function preloadImages() { 
  var d=document; 
  if(d.images)
  { 
	if(!d.pictures) d.pictures=new Array();

    	var i,j=d.pictures.length,a=preloadImages.arguments;
 
	for(i=0; i<a.length; i++)
    	  if (a[i].indexOf("#")!=0)
	  { 
	    d.picture[j]=new Image; 
	    d.pictures[j++].src=a[i];
	  }
  }
}

imgOn=new Array();
imgOff=new Array();
index=0;

function loadButton(name) {
	imgOn[index]=new Image(70,70);
	imgOn[index].src=name+"1.jpg";
	imgOff[index]=new Image(70,70);
	imgOff[index++].src=name+"0.jpg";
}
	

function on(name,index) {
	document[name].src=imgOn[index].src;
}

function off(name,index) {
	document[name].src=imgOff[index].src;
}