// add a new function
function addLoadEvent(func) {
	var oldonload = window.onload;
	if (typeof window.onload != 'function')
	{
		window.onload = func;
	}
	else
	{
		window.onload = function()
		{
			oldonload();
			func();
		}
	}
}

// plug html markup into document
function insertAfter(newElement, targetElement)
{
	var parent = targetElement.parentNode;
	if(parent.lastChild == targetElement)
	{
		parent.appendChild(newElement);
	}
	else
	{
		parent.insertBefore(newElement,targetElement.nextSibling);
	}
}

function rolloverLogo() 
{
	if (!document.getElementById) return false;
	if (!document.getElementById("logo")) return false;
	
	var logo = document.getElementById("logo");
	var preload = new Image()
	preload.src="images/nav/logo_on.png";
	
	logo.onmouseover = function()
	{
		logo.setAttribute("src","images/nav/logo_on.png");
	}
	logo.onmouseout = function()
	{
		logo.setAttribute("src","images/nav/logo_off.png");
	}
}

addLoadEvent(rolloverLogo);