//Sample
	//Params to pass Name of the layer and the array of the layer
	//<a href="#" onmouseover="layer_visible('Layer1',0)" OnMouseOut="layer_invisible('Layer1',0)">Test2 </a>
	isNS4 = (document.layers) ? true : false;
	isIE4 = (document.all && !document.getElementById) ? true : false;
	isIE5 = (document.all && document.getElementById) ? true : false;
	isNS6 = (!document.all && document.getElementById) ? true : false;
	
	sId = window.setTimeout("CheckLayers();",2500);
	
	function OpenLayer(Name)
	{
	   var LayerArray = new Array('Layer1', 'Layer2', 'Layer3', 'Layer4', 'Layer5');
	   var ImageArray = new Array('nav_data', 'nav_aboutus', 'nav_what', 'nav_news', 'nav_investor');
	   window.clearTimeout(sId);
	   for(var i=0; i < LayerArray.length;i++)
	   {//alert(i);
		if (isIE4)
		{
			if(LayerArray[i]==Name)
			{
				document.all[LayerArray[i]].style.visibility = "visible";
			}
			else if(LayerArray[i]!=Name)
			{
				document.all[LayerArray[i]].style.visibility = "hidden";
				changeImages(ImageArray[i], 'images/header/' + ImageArray[i] + '.gif'); 
			}
			
		}
		if (isNS4)
		{
		   	if(LayerArray[i]==Name)
		   	{
		   		document.layers[LayerArray[i]].visibility = "show";
		   	}
			else if
			(
				LayerArray[i]!=Name){document.layers[LayerArray[i]].visibility = "hide";
				changeImages(ImageArray[i], 'images/header/' + ImageArray[i] + '.gif'); 
			}
			//document.layers["Layer1"].visibility="show";
		}
		
		if (isIE5 || isNS6) 
		{
		   	  if(LayerArray[i]==Name)
		      {	elm = document.getElementById(LayerArray[i]);
		   		elm.style.visibility = "visible";
		   		
			  }
			  else if(LayerArray[i]!=Name)
			  { elm = document.getElementById(LayerArray[i]);
		   		elm.style.visibility = "hidden";
		   		changeImages(ImageArray[i], 'images/header/' + ImageArray[i] + '.gif'); 
			  }
		

		}
			
	   }sId = window.setTimeout("CheckLayers();",2500);
	}	
	
	function CheckLayers()
	{
		OpenLayer('');
	}