function getPosizioneVerticaleObj(obj)
{
	var curtop = 0;
	if(obj.offsetParent)
	{
		while(1)
		{
			curtop += obj.offsetTop;
			if(!obj.offsetParent)
			break;
			obj = obj.offsetParent;
		}
	}
	else if(obj.y)
	{
		curtop += obj.y;
	}
	return curtop;
}