function nurZahlen(str) {
    var val = str.value.replace(/[^\.^,\d]/g, '');
    str.value = val;
}

function OpenContact(seite) {
    var popup = window.open(seite, 'popup', 'width=450,height=350,location=no,resizable=yes,scrollbars=yes,menubar=no,status=no,toolbar=no');
    popup.focus(); 
    return true;
}

function CenterContact() {
    window.moveTo(((screen.width / 2) - (450 / 2)), ((screen.height / 2) - (350 / 2)));
    window.focus();
}