function enigma_sub_navigation_hover (side)
{
	var img;
	
	switch (side)
	{
		case "left":
			img = document.getElementById("enigma_sub_navigation_left");
			break;
		case "right":
			img = document.getElementById("enigma_sub_navigation_right");
			break;
	}
	
	if (img.src.indexOf("_on.jpg") != -1)
	{
		// turn it off
		img.src = img.src.replace("_on.jpg",".jpg");
	}
	else
	{
		// turn it on
		img.src = img.src.replace(".jpg","_on.jpg");
	}
}