var ie4 = (document.all)? true:false
var ns4 = (document.layers)? true:false
var ns6 = (document.getElementById && !document.all) ? true:false;

var temp		  = "";
var currentLayer  = "blankLayer";
var selectedLayer = "blankLayer";

function showLayer(layerName)
{
	if(currentLayer != "")
	{
		hideLayer(currentLayer);
	}
	
	if(ie4)
	{
		temp = eval(layerName + '.style');
		temp.visibility = 'visible';
		temp.display	= 'inline';
	}
	else if(ns6)
	{
		temp = eval('document.getElementById("'+layerName + '").style');
		temp.visibility = 'visible';
		temp.display	= 'inline';
	}
	else if(ns4)
	{
		temp = eval('document.'+layerName);
		temp.visibility = 'show';
		temp.display	= 'inline';
	}
	currentLayer = layerName;
}

function hideLayer(layerName)
{
	if(selectedLayer != layerName)
	{
		if(ie4)
		{
			temp = eval(layerName + '.style');
			temp.visibility = 'hidden';
			temp.display	= 'none';
		}
		else if(ns6)
		{
			temp = eval('document.getElementById("'+layerName + '").style');
			temp.visibility = 'hidden';
			temp.display	= 'none';
		}
		else if(ns4)
		{
			temp = eval('document.'+layerName);
			temp.visibility = 'hide';
			temp.display	= 'none';
		}
	}
}

function selectLayer(layerName)
{
	selectedLayer = layerName;
}