function switchImage(src, alt)
{
	var mainImage = document.getElementById("mainImage");
	
	if(mainImage == null) return;
	
	mainImage.src = src;
	mainImage.alt = alt;
}
function preloadImages()
{
	if(document.preloadImages == null)
	{
		document.preloadImages = new Array();
	}
	var length = document.preloadImages.length;
	for(var i = 0; i < arguments.length; i++)
	{
		document.preloadImages[length + i] = new Image();
		document.preloadImages[length + i].src = arguments[i];
	}
}