function chkFormular()
{
 if(document.Formular.vorname.value == "")
  {
   alert("Your first name please!");
   document.Formular.vorname.focus();
   return false;
  }
 if(document.Formular.nachname.value == "")
  {
   alert("Your surname name please!");
   document.Formular.nachname.focus();
   return false;
  }
 if(document.Formular.email.value == "")
  {
   alert("Your email please!");
   document.Formular.email.focus();
   return false;
  }
      if(document.Formular.email.value.indexOf('@') == -1)
  {
   alert("No valid email!");
   document.Formular.email.focus();
   return false;

  }
}