ns4 = (document.layers) ? 1:0;  
ie4 = (document.all)    ? 1:0;

function showLayer(whichLayer) {
        coordinates(whichLayer);
	if (ie4) { document.all[whichLayer].style.visibility="visible"; }
	if (ns4) { document.layers[whichLayer].visibility="visible"; }
}

function coordinates(whichLayer){

	if (ie4) {
		document.all[whichLayer].style.left=event.clientX+20;
		document.all[whichLayer].style.top=event.clientY-200;
	}

	if (ns4) {
		document.layers['one'].left=63;
		document.layers['one'].top=6;
		document.layers['two'].left=20;
		document.layers['two'].top=6;
	}
}

function hideLayer(whichLayer) {
	if (ie4) { document.all[whichLayer].style.visibility="hidden"; }
	if (ns4) { document.layers[whichLayer].visibility="hidden"; }
}