function swtch(num, imgname)
{
    if(document.images)
      document[imgname].src = img[num].src;
}

imgsrc = new Array();

imgsrc     [0] =  "../img/menu_pl/menu_01_off.gif",
imgsrc     [1] =  "../img/menu_pl/menu_01_on.gif",
imgsrc     [2] =  "../img/menu_pl/menu_02_off.gif",
imgsrc     [3] =  "../img/menu_pl/menu_02_on.gif",
imgsrc     [4] =  "../img/menu_pl/menu_03_off.gif",
imgsrc     [5] =  "../img/menu_pl/menu_03_on.gif",
imgsrc     [6] =  "../img/menu_pl/menu_04_off.gif",
imgsrc     [7] =  "../img/menu_pl/menu_04_on.gif",
imgsrc     [8] =  "../img/menu_pl/menu_05_off.gif",
imgsrc     [9] =  "../img/menu_pl/menu_05_on.gif",
imgsrc     [10] =  "../img/menu_pl/menu_06_off.gif",
imgsrc     [11] =  "../img/menu_pl/menu_06_on.gif",
imgsrc     [12] =  "../img/menu_pl/menu_07_off.gif",
imgsrc     [13] =  "../img/menu_pl/menu_07_on.gif",
imgsrc     [14] =  "../img/menu_pl/menu_08_off.gif",
imgsrc     [15] =  "../img/menu_pl/menu_08_on.gif",
imgsrc     [16] =  "../img/menu_pl/menu_09_off.gif",
imgsrc     [17] =  "../img/menu_pl/menu_09_on.gif"

if (document.images != null)
{
	img = new Array();
	for (i = 0; i < imgsrc.length; i++)
	{
	img[i] = new Image();
	img[i].src = imgsrc[i];
	}
}