var ie=document.all && !window.opera
		var lastImage = "image1";
		function turnOn(image_id,change)
		{
			if(change)
			{
				curImage = lastImage;
				lastImage = image_id;
				turnOff(curImage);
			}
			if(!ie)
			{
				document.getElementById(image_id).style.opacity=1;
			}
			else
			{
				document.getElementById(image_id).filters.alpha.opacity=100;
			}
		}
		
		function turnOff(image_id)
		{
			if(image_id!=lastImage)
			{
				if(!ie)
				{
					document.getElementById(image_id).style.opacity=0.4;
				}
				else
				{
					document.getElementById(image_id).filters.alpha.opacity=40;
				}
			}
		}