userAgent = window.navigator.userAgent;
browserVers = parseInt(userAgent.charAt(userAgent.indexOf("/")+1),10);
function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function findElement(n,ly) {
	if (browserVers < 4)		return document[n];
	var curDoc = ly ? ly.document : document;
	var elem = curDoc[n];
	if (!elem) {
		for (var i=0;i<curDoc.layers.length;i++) {
			elem = findElement(n,curDoc.layers[i]);
			if (elem) return elem;
		}
	}
	return elem;
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		var img;
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			img = null;
			if (document.layers) {
				img = findElement(changeImages.arguments[i],0);
			}
			else {
				img = document.images[changeImages.arguments[i]];
			}
			if (img) {
				img.src = changeImages.arguments[i+1];
			}
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		mainnavi_01_over = newImage("images/mainnavi_01-over.gif");
		mainnavi_03_over = newImage("images/mainnavi_03-over.gif");
		mainnavi_05_over = newImage("images/mainnavi_05-over.gif");
		mainnavi_07_over = newImage("images/mainnavi_07-over.gif");
		mainnavi_09_over = newImage("images/mainnavi_09-over.gif");
		mainnavi_11_over = newImage("images/mainnavi_11-over.gif");
		mainnavi_13_over = newImage("images/mainnavi_13-over.gif");
		mainnavi_15_over = newImage("images/mainnavi_15-over.gif");
		mainnavi_17_over = newImage("images/mainnavi_17-over.gif");
		subnavi1_01_over = newImage("images/subnavi1_01-over.gif");
		subnavi1_02_over = newImage("images/subnavi1_02-over.gif");
		subnavi2_01_over = newImage("images/subnavi2_01-over.gif");
		subnavi2_02_over = newImage("images/subnavi2_02-over.gif");
		subnavi2_03_over = newImage("images/subnavi2_03-over.gif");
		subnavi2_04_over = newImage("images/subnavi2_04-over.gif");
		subnavi3_01_over = newImage("images/subnavi3_01-over.gif");
		subnavi3_02_over = newImage("images/subnavi3_02-over.gif");
		subnavi3_03_over = newImage("images/subnavi3_03-over.gif");
		subnavi3_04_over = newImage("images/subnavi3_04-over.gif");
		subnavi3_05_over = newImage("images/subnavi3_05-over.gif");
		subnavi3_06_over = newImage("images/subnavi3_06-over.gif");
		subnavi4_01_over = newImage("images/subnavi4_01-over.gif");
		subnavi4_02_over = newImage("images/subnavi4_02-over.gif");
		subnavi4_03_over = newImage("images/subnavi4_03-over.gif");
		subnavi4_04_over = newImage("images/subnavi4_04-over.gif");
		subnavi4_05_over = newImage("images/subnavi4_05-over.gif");
		subnavi4_06_over = newImage("images/subnavi4_06-over.gif");
		preloadFlag = true;
	}
}