// set global browser identification variables
		browser = navigator.appName;
		browserNum = parseInt(navigator.appVersion);
		N4 = false;
		N6 = false;
		IE = false;
		
		if ((browser == "Netscape") && (browserNum < 5))
		{
			// Netscape 4.x
			layerRef = "document.layers['";
			endLayerRef = "']";
			styleRef = "";
			N4 = true;
		}
		else if ((browser == "Netscape") && (browserNum >= 5))
		{
			// Netscape 6
			layerRef = "document.getElementById('";
			styleRef = ".style";
			endLayerRef = "')";
			N6 = true;
		}
		else
		{
			// Internet Explorer
			layerRef = "document.all['";
			endLayerRef = "']";
			styleRef = ".style";
			IE = true;
		}
		
		// create way to remember which layer is visible
		oldLayer = "none";
		
		// set animation variables
		initialTop = 130;
		newTop = initialTop;
		
		function showMenu(layerName)
		{
			// show the layer the user wants to see
			eval(layerRef + layerName + endLayerRef + styleRef + ".visibility = 'visible'");
			
			
			// move other window
			if (oldLayer != "none")
			{
				// alter z-indices of layers to place
				// the new menu above older menu
				eval(layerRef + layerName + endLayerRef + styleRef + ".zIndex = 8");
				eval(layerRef + oldLayer + endLayerRef + styleRef + ".zIndex = 10");
				
				// slide the old menu layer up and out of sight
				slideMenu(oldLayer);
			}
			
			
			// update which window is currently visible
			if (oldLayer == layerName)
			{
				oldLayer = "none";
			}
			else
			{
				oldLayer = layerName;
			}
			
		}
		
		function slideMenu(layerName)
		{
			// find layer height
			if(N4)
			{
				height = eval(layerRef + layerName + endLayerRef + ".clip.height");
			}
			else
			{
				height = eval(layerRef + layerName + endLayerRef + ".offsetHeight");
			}
			
			// animate the layer upwards
			moveLayer(layerName,height);

			return;
		}
		
		
		
		function moveLayer(layerName,height)
		{
			// newTop and initialTop are global variables, set earlier
			endTop = initialTop - height;
			newHeight = height - newTop;
			
			if(newTop > endTop)
			{
				// move layer again
				newTop = newTop - 20;
				eval(layerRef + layerName + endLayerRef + styleRef + ".top = " + newTop);
				//eval(layerRef + layerName + endLayerRef + ".offsetHeight = " + newHeight);
			}
			else
			{
				// hide the old menu and reset its position
				eval(layerRef + layerName + endLayerRef + styleRef + ".visibility = 'hidden'");
				eval(layerRef + layerName + endLayerRef + styleRef + ".top = " + initialTop);
				
				// reset global variable in preparation for the next menu
				newTop = initialTop;
				return;
			}

			// wait a bit, then call this function again
			setTimeout("moveLayer('" + layerName + "'," + height + ")",1);
		}