function Form_Validator(form)
  {
    // alert("Form Validation");

    // if (form.sub_time.value == "")
    // {
    //   alert("Please specify the length of your subscription");
    //   form.sub_time.focus();
    //   return (false);
    // }

    re = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/ ;

    if (re.test (form.email.value) == false)
    {
      alert("Please specify a valid e-mail address");
      form.email.focus();
      return (false);
    }

    // mystring = new String(form.s_userid.value);

    // if (mystring.length < 2)
    // {
    //   alert("Please specify a valid username");
    //   form.s_userid.focus();
    //   return (false);
    // }

    mystring = new String(form.s_passwd.value);

    if (mystring.length < 6)
    {
      alert("Please specify a valid password");
      form.s_passwd.focus();
      return (false);
    }

    if (form.first_name.value == "")
    {
      alert("Please specify your first name");
      form.first_name.focus();
      return (false);
    }

    if (form.last_name.value == "")
    {
      alert("Please specify your last name");
      form.last_name.focus();
      return (false);
    }

    if (form.address1.value == "")
    {
      alert("Please specify your address");
      form.address1.focus();
      return (false);
    }

    if (form.city.value == "")
    {
      alert("Please specify your city");
      form.city.focus();
      return (false);
    }

    if (form.state.value == "")
    {
      alert("Please specify your state");
      form.state.focus();
      return (false);
    }

    if (form.zip.value == "")
    {
      alert("Please specify your zip code");
      form.zip.focus();
      return (false);
    }

    return (true);
  }



  // Original:  Simon Tneoh (tneohcb@pc.jaring.my)
  //
  // This script and many more are available free online at
  // The JavaScript Source!! http://javascript.internet.com
  //
  //  http://javascript.internet.com/forms/val-credit-card.html


  var Cards = new makeArray(8);

  Cards[0] = new CardType("MasterCard", "51,52,53,54,55", "16");
  var MasterCard = Cards[0];

  Cards[1] = new CardType("VisaCard", "4", "13,16");
  var VisaCard = Cards[1];

  Cards[2] = new CardType("AmExCard", "34,37", "15");
  var AmExCard = Cards[2];

  Cards[3] = new CardType("DinersClubCard", "30,36,38", "14");
  var DinersClubCard = Cards[3];

  Cards[4] = new CardType("DiscoverCard", "6011", "16");
  var DiscoverCard = Cards[4];

  Cards[5] = new CardType("enRouteCard", "2014,2149", "15");
  var enRouteCard = Cards[5];

  Cards[6] = new CardType("JCBCard", "3088,3096,3112,3158,3337,3528", "16");
  var JCBCard = Cards[6];

  var LuhnCheckSum = Cards[7] = new CardType();


  // CheckCardNumber(form)
  //
  //	function called when users click the "submit" button.

  function CheckCardNumber(form)
  {
    var tmpyear;

    if (form.cc_type.value == "")
    {
      alert("Please specify your method of payment");
      form.cc_type.focus();
      return false;
    }

    if (form.cc_number.value == "")
    {
      alert("Please specify a credit card number");
      form.cc_number.focus();
      return false;
    }

    if (form.cc_code.value == "")
    {
      alert("Please specify a credit card ID number");
      form.cc_code.focus();
      return false;
    }

    if (form.cc_exp_month.value == "" || form.cc_exp_year.value == "")
    {
      alert("Please specify your credit card expiration date.");
      form.cc_exp_month.focus();
      return false;
    }

    tmpmonth = form.cc_exp_month.value;
    tmpyear = form.cc_exp_year.value;

    // The following line doesn't work in IE3, you need to change it
    // to something like "(new CardType())...".
    // if (!CardType().isExpiryDate(tmpyear, tmpmonth)) (open paren)

    if (!(new CardType()).isExpiryDate(tmpyear, tmpmonth))
    {
      alert("This card has already expired.");
      return false;
    }

    card = form.cc_type.options[form.cc_type.selectedIndex].value;

    var retval = eval(card + ".checkCardNumber(\"" + form.cc_number.value +
				"\", " + tmpyear + ", " + tmpmonth + ");");

    cardname = "";

    if (retval)
    {
      // comment this out if used on an order form

      // alert("This card number appears to be valid.");
      return true;
    }
    else
    {
      // The cardnumber has the valid luhn checksum, but we
      // want to know which cardtype it belongs to.

      for (var n = 0; n < Cards.size; n++)
      {
        if (Cards[n].checkCardNumber(form.cc_number.value, tmpyear, tmpmonth))
        {
          cardname = Cards[n].getCardType();
          break;
        }
      }

      if (cardname.length > 0)
      {
        alert("This looks like a " + cardname + " number, not a " +
			card + " number.");
        return false;
      }
      else
      {
        alert("Please specify a valid credit card number");
        return false;
      }
    }

    return true;
  }


  // Object CardType([String cardtype, String rules, String len,
  //						int year, int month])
  //	cardtype    : type of card, eg: MasterCard, Visa, etc.
  //	rules       : rules of the cardnumber, eg: "4", "6011", "34,37".
  //	len         : valid length of cardnumber, eg: "16,19", "13,16".
  //	year        : year of expiry date.
  //	month       : month of expiry date.
  //	eg:
  //	var VisaCard = new CardType("Visa", "4", "16");
  //	var AmExCard = new CardType("AmEx", "34,37", "15");

  function CardType()
  {
    var n;
    var argv = CardType.arguments;
    var argc = CardType.arguments.length;

    this.objname = "object CardType";

    var tmpcardtype = (argc > 0) ? argv[0] : "CardObject";
    var tmprules = (argc > 1) ? argv[1] : "0,1,2,3,4,5,6,7,8,9";
    var tmplen = (argc > 2) ? argv[2] : "13,14,15,16,19";

    this.setCardNumber = setCardNumber;	// set CardNumber method.
    this.setCardType = setCardType;	// setCardType method.
    this.setLen = setLen;		// setLen method.
    this.setRules = setRules;		// setRules method.
    this.setExpiryDate = setExpiryDate;	// setExpiryDate method.


    this.setCardType(tmpcardtype);
    this.setLen(tmplen);
    this.setRules(tmprules);

    if (argc > 4)
    {
      this.setExpiryDate(argv[3], argv[4]);
    }

    this.checkCardNumber = checkCardNumber;  // checkCardNumber method.
    this.getExpiryDate = getExpiryDate;  // getExpiryDate method.
    this.getCardType = getCardType;  // getCardType method.
    this.isCardNumber = isCardNumber;  // isCardNumber method.
    this.isExpiryDate = isExpiryDate;  // isExpiryDate method.
    this.luhnCheck = luhnCheck;// luhnCheck method.

    return this;
  }


  // boolean checkCardNumber([String cardnumber, int year, int month])
  //
  //	return true if cardnumber pass the luhncheck and the expiry date is
  //	valid, else return false.

  function checkCardNumber()
  {
    var argv = checkCardNumber.arguments;
    var argc = checkCardNumber.arguments.length;
    var cardnumber = (argc > 0) ? argv[0] : this.cardnumber;
    var year = (argc > 1) ? argv[1] : this.year;
    var month = (argc > 2) ? argv[2] : this.month;


    this.setCardNumber(cardnumber);
    this.setExpiryDate(year, month);

    if (!this.isCardNumber())
    {
      return false;
    }

    if (!this.isExpiryDate())
    {
      return false;
    }

    return true;
  }


  // String getCardType()
  //
  //	return the cardtype.

  function getCardType()
  {
    return this.cardtype;
  }


  // String getExpiryDate()
  //
  //	return the expiry date.

  function getExpiryDate()
  {
    return this.month + "/" + this.year;
  }


  // boolean isCardNumber([String cardnumber])
  //
  //	return true if cardnumber pass the luhncheck and the rules,
  //	else return false.

  function isCardNumber()
  {
    var argv = isCardNumber.arguments;
    var argc = isCardNumber.arguments.length;
    var cardnumber = (argc > 0) ? argv[0] : this.cardnumber;


    if (!this.luhnCheck())
    {
      return false;
    }

    for (var n = 0; n < this.len.size; n++)
    {
      if (cardnumber.toString().length == this.len[n])
      {
        for (var m = 0; m < this.rules.size; m++)
        {
          var headdigit =
		cardnumber.substring(0, this.rules[m].toString().length);

          if (headdigit == this.rules[m])
          {
            return true;
          }
        }

        return false;
      }
    }

    return false;
  }


  // boolean isExpiryDate([int year, int month])
  //
  //	return true if the date is a valid expiry date,
  //	else return false.

  function isExpiryDate()
  {
    var argv = isExpiryDate.arguments;
    var argc = isExpiryDate.arguments.length;


    year = argc > 0 ? argv[0] : this.year;
    month = argc > 1 ? argv[1] : this.month;

    if (!isNum(year+""))
    {
      return false;
    }

    if (!isNum(month+""))
    {
      return false;
    }

    today = new Date();
    expiry = new Date(year, month);

    if (today.getTime() > expiry.getTime())
    {
      return false;
    }
    else
    {
      return true;
    }
  }


  // boolean isNum(String argvalue)
  //
  //	return true if argvalue contains only numeric characters,
  //	else return false.

  function isNum(argvalue)
  {
    argvalue = argvalue.toString();

    if (argvalue.length == 0)
    {
      return false;
    }

    for (var n = 0; n < argvalue.length; n++)
    {
      if (argvalue.substring(n, n+1) < "0" || argvalue.substring(n, n+1) > "9")
      {
        return false;
      }
    }

    return true;
  }


  // boolean luhnCheck([String CardNumber])
  //
  //	return true if CardNumber pass the luhn check else return false.
  //	Reference: http://www.ling.nwu.edu/~sburke/pub/luhn_lib.pl

  function luhnCheck()
  {
    var argv = luhnCheck.arguments;
    var argc = luhnCheck.arguments.length;

    var CardNumber = argc > 0 ? argv[0] : this.cardnumber;

    if (! isNum(CardNumber))
    {
      return false;
    }


    var no_digit = CardNumber.length;
    var oddoeven = no_digit & 1;
    var sum = 0;

    for (var count = 0; count < no_digit; count++)
    {
      var digit = parseInt(CardNumber.charAt(count));

      if (!((count & 1) ^ oddoeven))
      {
        digit *= 2;

        if (digit > 9)
        {
          digit -= 9;
        }
      }

      sum += digit;
    }

    if (sum % 10 == 0)
    {
      return true;
    }
    else
    {
      return false;
    }
  }


  // ArrayObject makeArray(int size)
  //
  //	return the array object in the size specified.

  function makeArray(size)
  {
    this.size = size;

    return this;
  }


  // CardType setCardNumber(cardnumber)
  //
  //	return the CardType object.

  function setCardNumber(cardnumber)
  {
    this.cardnumber = cardnumber;
    return this;
  }


  // CardType setCardType(cardtype)
  //
  //	return the CardType object.

  function setCardType(cardtype)
  {
    this.cardtype = cardtype;
    return this;
  }


  // CardType setExpiryDate(year, month)
  //
  //	return the CardType object.

  function setExpiryDate(year, month)
  {
    this.year = year;
    this.month = month;
    return this;
  }


  // CardType setLen(len)
  //
  //	return the CardType object.

  function setLen(len)
  {
    // Create the len array.

    if (len.length == 0 || len == null)
    {
      len = "13,14,15,16,19";
    }

    var tmplen = len;

    n = 1;
    while (tmplen.indexOf(",") != -1)
    {
      tmplen = tmplen.substring(tmplen.indexOf(",") + 1, tmplen.length);
      n++;
    }

    this.len = new makeArray(n);
    n = 0;
    while (len.indexOf(",") != -1)
    {
      var tmpstr = len.substring(0, len.indexOf(","));

      this.len[n] = tmpstr;
      len = len.substring(len.indexOf(",") + 1, len.length);
      n++;
    }

    this.len[n] = len;

    return this;
  }


  // CardType setRules()
  //
  //	return the CardType object.

  function setRules(rules)
  {
    // Create the rules array.

    if (rules.length == 0 || rules == null)
    {
      rules = "0,1,2,3,4,5,6,7,8,9";
    }
  
    var tmprules = rules;

    n = 1;
    while (tmprules.indexOf(",") != -1)
    {
      tmprules = tmprules.substring(tmprules.indexOf(",") + 1, tmprules.length);
      n++;
    }

    this.rules = new makeArray(n);
    n = 0;
    while (rules.indexOf(",") != -1)
    {
      var tmpstr = rules.substring(0, rules.indexOf(","));

      this.rules[n] = tmpstr;
      rules = rules.substring(rules.indexOf(",") + 1, rules.length);
      n++;
    }

    this.rules[n] = rules;
    return this;
  }