Advanced e-mail validation?

[c4n]

In my CGI scripts I validate u-mail so that I check for a dot "." and a "@". Like this:

unless ($email=~/\@/ && $email=~/\./) {
&error;
exit;
};

The problem is people can still enter a not-working e-mail (like this one: asfaasd@asdasf.com) but the script will not detect this.

Is there a way to ... hmmm ... "make" the MAIL PROGRAM check if this e-mail is actually working?

I'm using Sendmail and tried with some switches but allways get that lovely "500 Internal server error" message.

Here is a link to Sendmail switches (a very useful resource):

http://www.redhat.com/support/resources/howto/RH-sendmail-HOWTO/c420.html#AEN423

The -bt and -bv are used for e-mail validation but like said, I hadn't had any luck yet.

Can anyone help me out? Perhaps you have some other ideas or tricks for "advanced" e-mail validation?

A HUGE thanks in advance!

 

[NEVERSLEEP]

#!perl -W
use Mail::CheckUser qw(check_email);

my $email = "someone\@somewhere.com";

if(check_email($email)) {
print &quot;E-mail address <&quot; . $email . &quot;> is OK&quot;;
} else {
print &quot;E-mail address <&quot; . $email . &quot;> isn't valid&quot;;
}

exit;
# example with : Mail::CheckUser 1.02 ---------------------------------------

someone knowledge ends where
someone else knowledge starts

 

[Haunter]

A second possibility is to mail them a random password or access key to the provided email. Then have them send it back to you and continue process the rest of the program when the passkey is supplied.