function disableEnterKey() {
	if (window.event.keyCode == 13)
		window.event.keyCode = 0;
	}

var hilited_field_backgroundColor = "#CCFFFF";


function checkform() {
	
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,6})+$/;
	
	var emaildomain = document.kontakt.email.value.split('@');

	if (document.kontakt.name.value == "" || document.kontakt.email.value == "" || document.kontakt.text.value == "") {
		document.getElementById('name').style.backgroundColor = hilited_field_backgroundColor;
		document.getElementById('email').style.backgroundColor = hilited_field_backgroundColor;
		document.getElementById('text').style.backgroundColor = hilited_field_backgroundColor;
		alert("Erforderliche Felder sind leer.");
		return false;
		}
	else if (!filter.test(document.kontakt.email.value)) {
		document.getElementById('email').style.backgroundColor = hilited_field_backgroundColor;
		alert('Ungültige eMail-Adresse.');
		return false;
		}

	else if (emaildomain[1]=='gmail.com') {
		document.getElementById('email').style.backgroundColor = hilited_field_backgroundColor;
		alert('Wegen zu hohen Spamaufkommens sind gmail.com Adressen momentan gesperrt.');
		return false;
		}
	
	else
		return true;

	}