function validInput(data,type,length)
{
  switch (type)
  {
    case "float": 
    { 
      var charpos = data.value.search("[^0-9.]");
      if(data.value.length > 0 && charpos >= 0) 
        return false; 
      if ((length != undefined) && (data.value.length != length))
        return false;
      if (data.value < 5)
        return false;
      break; 
    }
  }
  return true;
}
  
function donate()
{
  obj = document.forms['_xclick'];

  message = "";
  if (!validInput(obj.amount, "float"))
  {
    message += "Please enter an amount of 5 dollars or greater\n";
  }
  
  if (message.length > 0)
  {
    alert(message);
    return false;
  }

  reserveObj.submit();
}