window.onload = function ()
{
	var logoList = document.getElementById('logoSet').getElementsByTagName('IMG');
	
	var preloadList = new Array();
	for (var i=0; i < logoList.length; i++)
	{
		preloadList[i] = new Image();
		preloadList[i].src = logoList[i].src.replace('_gray','');
	}
	
	document.getElementById('logoSet').onmouseout = document.getElementById('logoSet').onmouseover = function(e)
	{
		e = e ? e : window.event;
		var elem = e.target ? e.target : e.srcElement;
		
		if (elem.tagName=="IMG")
		{
			if (e.type == 'mouseover') elem.src = elem.src.replace('_gray','');
			else elem.src = elem.src.replace('.png', '_gray.png');
		}
	};
};