var iscached = false;

function cacheImages(object)	{
	for (var i = 1; i < cacheImages.arguments.length; i++)	{
   		eval(cacheImages.arguments[i] + "_on = new Image(); " + cacheImages.arguments[i] + "_on.src = '" + cacheImages.arguments[0]  + cacheImages.arguments[i] + "_on.jpg';");
   		eval(cacheImages.arguments[i] + "_off = new Image(); " + cacheImages.arguments[i] + "_off.src = '" + cacheImages.arguments[0]  + cacheImages.arguments[i] + "_off.jpg';");
	}	
	iscached = true;
}

function rollOn(imageId)	{
	if (iscached)	{
	eval("document.images['" + imageId + "'].src = " + imageId + "_on.src;");
	} 
}

function rollOff(imageId)	{
	if (iscached)	{
	eval("document.images['" + imageId + "'].src = " + imageId + "_off.src;");
	}
}