var HoverMenuItemId = -1;

function InvertHoverImage(HoverMenuItem) {
	var sfEls = document.getElementById(HoverMenuItem).getElementsByTagName("img");
	for (var i=0; i<sfEls.length; i++) 
	{
		if (sfEls[i].className == "img_normal")
		{
			sfEls[i].className = "img_hover";
		}
		else
			if (sfEls[i].className == "img_hover")
			{
				sfEls[i].className = "img_normal";
			}
	}
}