Form Validatioin

Hi

I have been having a lot of trouble of late with somebody trying to use my

form script to send Spam.

I have tried to lock them out but they keep changing IP address and I
can't 
so
I have removed following line to stop the emails, but I still get crap 
though

$headers .= "From:$Email <$Contact_Name>\n";

So I am now going to have to look at a better way of Form Validation

I found this script on the net to validate the email address, seem to work

fine (see below)

I now want to add two extra things

First, apart from the email address all the other fields are either
string, 
numbers or a combination,
they should never have anything else that, below is an example of what I
am 
getting through,
what's the best way to stop this?

counthry Content-Type: multipart/alternative; 
boundary=244c370b70207220fc95267404de5752 MIME-Version: 1.0 Subject: s
bcc: 
bressg6@[EMAIL PROTECTED]
 This is a multi-part message in MIME 
format. --244c370b70207220fc95267404de5752 Content-Type: text/plain; 
charset=\"us-ascii\" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit in
th 
shape iv an advance payment on th dowry. t fifteen quit stoppin runaway 
horses as on y suited to childher. fter that wint in almost entirely f r 
knockin down arnychists as they was about to shoot. 
saved --244c370b70207220fc95267404de5752-- .

Second, can anybody point me in the right direction to add one of those 
things where the user has to type in a number, but the number is shown as
a 
distorted graphic I'm guessing I need to set a cookie or something and
they 
test for it when the user types in the number. It there a graphic library
to 
do this?

Thanks

Brian



function checkaddaddress($email) {
   // First, we check that there's one @[EMAIL PROTECTED]
 symbol, and that the lengths are 
right
      if (!ereg("^[^@[EMAIL PROTECTED]
", $email)) {
        // Email invalid because wrong number of characters in one
section, 
or wrong number of @[EMAIL PROTECTED]
 symbols.
        return false;
      }
      // Split it into sections to make life easier
      $email_array = explode("@[EMAIL PROTECTED]
", $email);
      $local_array = explode(".", $email_array[0]);
      for ($i = 0; $i <sizeof($local_array); $i++) {
        if 
(!ereg("^(([A-Za-z0-9!#$%&'*+/=?^_`{|}~-][A-Za-z0-9!#$%&'*+/=?^_`{|}~\.-]{0,63})|(\"[^(\\|\")]{0,62}\"))$",

$local_array[$i])) {
          return false;
        }
      }
      if (!ereg("^\[?[0-9\.]+\]?$", $email_array[1])) { // Check if domain

is IP. If not, it should be valid domain name
        $domain_array = explode(".", $email_array[1]);
        if (sizeof($domain_array) <2) {
          return false; // Not enough parts to domain
        }
        for ($i = 0; $i <sizeof($domain_array); $i++) {
          if 
(!ereg("^(([A-Za-z0-9][A-Za-z0-9-]{0,61}[A-Za-z0-9])|([A-Za-z0-9]+))$", 
$domain_array[$i])) {
            return false;
          }
        }
      }
    return true;
    }