function testzahl(wert) {
 if (wert < 39.90 || isNaN(wert)) {
    alert("Please donate a reasonable amount. Thank you.");
    document.vorgabe.amount.focus();
    return false;
  }
  return true;
}


function gopaypal() {
  document.vorgabe.amount.value = document.vorgabe.amount.value.replace(/,/,".");
  document.vorgabe.amount.value = Math.abs(document.vorgabe.amount.value);
  if (testzahl(document.vorgabe.amount.value)) {
    document.paypal.action="https://www.paypal.com/us/cgi-bin/webscr";
    document.paypal.amount.value=document.vorgabe.amount.value;
    document.paypal.item_name.value="Ceausescu - The DVDs vs. CARE Project Donation";
    document.paypal.submit();
    return true;
  }
  return false;
}