function onLoad()
{
	window.onresize = setMainDivPos;
	window.setMainDivPos();
}

function setMainDivPos()
{
	var mainDiv = document.getElementById('root_maindiv');

	if(document.documentElement)
	{
		var posY = (document.documentElement.clientHeight / 2) - 275;
		if(posY < 0)
			posY = 0;
		mainDiv.style.margin = posY + "px auto 0px auto";
	}
	else if(document.body)
	{
		var posY = (document.body.clientHeight / 2) - 275;
		if(posY < 0)
			posY = 0;
		mainDiv.style.margin = posY + "px auto 0px auto";
	}
	else if(window.screen) 
	{
		var posY = ((window.screen.availHeight / 2) - 295);
		if(posY < 0)
			posY = 0;
		mainDiv.style.margin = posY + "px auto 0px auto";
	}	
}