function fcheck()
{
    var mes = "";

    if(document.fi.name.value == "" || document.fi.email.value == "" || document.fi.mitteilung.value == "")
    {
        mes += "Please fill in all required fields! \n\n";
    }

    if(mes)
    {
        alert(mes);

        return false;
    }
    else
    {
        return true;
    }
}