function check_form_contact_data(form) {
	buffer = ""; 
	if (form.name.value == "") {
		buffer += " 'Name' "
	}
	if (form.email.value == "") {
		buffer += " 'E-Mail-Adresse' "
	}
	if (form.message.value == "") {
		buffer += " 'Anschreiben' "
	}
	if (buffer != "") {
		alert("Bitte füllen Sie die Pflichtfelder aus! "+buffer);
		return false; 
	}
	return true ;
}