//self.resizeTo(800,600);

function authentication(form)
{
    vLogin = form.logged_username.value;
    if ((vLogin == "")||(vLogin.toUpperCase() == "ADMIN"))
    {
        alert("Terá de inserir um login válido!");
        return false;
    }
    vPassword = form.logged_user_password.value;
    if (vPassword == "")
    {
        alert("Terá de inserir uma palavra passe válida!");
        return false;
    }
    return true;
}

function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() 
{
	if (document.images && (preloadFlag == true))
	{
		for (var i=0; i<changeImages.arguments.length; i+=2)
		{
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() 
{
	if (document.images) 
	{
		A_empresa_01_over = newImage("images/A-empresa_01-over.gif");
		A_empresa_01_down = newImage("images/A-empresa_01-down.gif");
		Novidades_01_over = newImage("images/Novidades_01-over.gif");
		Novidades_01_down = newImage("images/Novidades_01-down.gif");
		Catalogo_01_over = newImage("images/Catalogo_01-over.gif");
		Catalogo_01_down = newImage("images/Catalogo_01-down.gif");
		Encomendas_01_over = newImage("images/Encomendas_01-over.gif");
		Encomendas_01_down = newImage("images/Encomendas_01-down.gif");
		Portugues_01_over = newImage("images/Portugues_01-over.gif");
		Portugues_01_down = newImage("images/Portugues_01-down.gif");
		Espanhol_01_over = newImage("images/Espanhol_01-over.gif");
		Espanhol_01_down = newImage("images/Espanhol_01-down.gif");
		Ingles_01_over = newImage("images/Ingles_01-over.gif");
		Ingles_01_down = newImage("images/Ingles_01-down.gif");												
		preloadFlag = true;
	}
}