var imageRollover = {
	
	main : function() {
		var img = document.images, ipt = document.getElementsByTagName('input'), i, preLoadImg = [];
		// img elements
		for (i = 0; i <img.length; i++) {
			if ((img[i].src.match(/.*_off\./))||(img[i].style.filter)){
				preLoadImg[preLoadImg.length] = new Image;
				preLoadImg[preLoadImg.length-1].src = img[i].src.replace('_off.', '_on.');

				img[i].onmouseover = imageRollover.over;
				img[i].onmouseout  = imageRollover.out;
				try {img[i].addEventListener('click', imageRollover.click, false);}
				catch(e){img[i].attachEvent('onclick', (function(el){return function(){imageRollover.click.call(el);};})(img[i]));}
			}
		}
		// input[image] elements
		for (i = 0; i <ipt.length; i++) {
			if ((ipt[i].src.match(/.*_off\./))&&(ipt[i].getAttribute('type')=='image')){
				preLoadImg[preLoadImg.length] = new Image;
				preLoadImg[preLoadImg.length-1].src = img[i].src.replace('_off.', '_no.');

				ipt[i].onmouseover = imageRollover.over;
				ipt[i].onmouseout  = imageRollover.out;
				try {ipt[i].addEventListener('click', imageRollover.click, false);}
				catch(e){ipt[i].attachEvent('onclick', (function(el){return function(){imageRollover.click.call(el);};})(ipt[i]));}
			}
		}
	}
	,
	
	over : function() {
		var imgSrc, preLoadImgSrc;
		if((this.style.filter)&&(this.style.filter.match(/_off\.png/)))//(IE5.5-6 && png)
			this.style.filter = this.style.filter.replace('_off.png', '_on.png');
		else
			this.src = this.src.replace('_off.', '_on.');
	},

	out : function(){
		if((this.style.filter)&&(this.style.filter.match(/_on\.png/)))//(IE5.5-6 && png)
			this.style.filter = this.style.filter.replace('_on.png', '_off.png');
		else
			this.src = this.src.replace('_on.', '_off.');
	},
	
	click : function(){
		if((this.style.filter)&&(this.style.filter.match(/_on\.png/)))//(IE5.5-6 && png)
			this.style.filter = this.style.filter.replace('_on.png', '_off.png');
		else
			this.src = this.src.replace('_on.', '_off.');
	},

	addEvent : function(){
		try {
			window.addEventListener('load', this.main, false);
		} catch (e) {
			window.attachEvent('onload', this.main);
		}
	}
}

imageRollover.addEvent();

// scrolling page top
function backToTop() {
	var x1 = x2 = x3 = 0;
	var y1 = y2 = y3 = 0;
		if (document.documentElement) {
		x1 = document.documentElement.scrollLeft || 0;
		y1 = document.documentElement.scrollTop || 0;
	}
	if (document.body) {
		x2 = document.body.scrollLeft || 0;
		y2 = document.body.scrollTop || 0;
	}
	x3 = window.scrollX || 0;
	y3 = window.scrollY || 0;
	var x = Math.max(x1, Math.max(x2, x3));
	var y = Math.max(y1, Math.max(y2, y3));
	window.scrollTo(Math.floor(x / 2), Math.floor(y / 2));
	if (x > 0 || y > 0) {
	window.setTimeout("backToTop()", 25);
	}
}