function ausgefuellt(text) {
 	if (text == "hier") { return false };
 return (text.length > 1); // mindestens zwei Buchstaben
}

function pruefe_email(address) {
  if ((address == "")
    || (address.indexOf ('@') == -1)
    || (address.indexOf ('.') == -1))
      return false;
  return true;
}
function ist_zahl(eingabe) {
	for(i=0; i < eingabe.length; ++i) {
	   if (eingabe.charAt(i) < "0" || eingabe.charAt(i) > "9")	return false;
	}
	return true;
}


function also(feld,text) {
        ist_ok = false;
        alert(text);
        document.form1[feld].value = "";
        document.form1[feld].focus();
        document.form1[feld].select();
  return ist_ok;
}


function checkMailForm() {
    if (checkForm()) {
                    prev_big();
                    return false;
                    }
    else {
            return false;
        }
}

function checkForm() {
	ist_ok = true;
	if (!ausgefuellt(document.form1.surname.value))  { also('surname','Surname missing!'); return false; }
	if (!ausgefuellt(document.form1.firstname.value))  { also('firstname','First name missing!'); return false; }
	if (!ausgefuellt(document.form1.street.value))  { also('street','Street missing!'); return false; }
    if (!ausgefuellt(document.form1.town.value))  { also('town','Town missing!'); return false; }
	if (!ausgefuellt(document.form1.county.value))  { also('county','County missing!'); return false; }
    if (!ausgefuellt(document.form1.postcode.value))  { also('postcode','Postcode missing!'); return false; }
    if (!ausgefuellt(document.form1.email.value))  { also('email','E-mail missing!'); return false; }
	if (!pruefe_email(document.form1.email.value))   { also('email','E-mail missing!'); return false; }
    if (!ausgefuellt(document.form1.questions.value))  { also('questions','Question missing'); return false; }
	
    return ist_ok;

}