function ChangeColors(objName, color1, color2)
	{
		var rows = document.getElementById(objName).getElementsByTagName("tr");
		var n = rows.length;
		var colorCode= color1
		for(var i=0; i<n; ++i)
		{
			rows[i].style.backgroundColor = colorCode ;
			if (colorCode == color1  )
				colorCode = color2
			else
				colorCode = color1
		}
	}