Your task smells like spamming. However, for validating address I usually use this:
sub validate_email_address {
my $addr_to_check = shift;
$addr_to_check =~ s/("(?:[^"\\]|\\.)*"|[^\t "]*)[ \t]*/$1/g;
my $esc = '\\\\';
my $space = '\040';
my $ctrl = '\000-\037';
my $dot = '\.';
my $nonASCII = '\x80-\xff';
my $CRlist = '\012\015';
my $letter = 'a-zA-Z';
my $digit = '\d';
my $atom_char = qq{ [^$space<>\@,;:".\\[\\]$esc$ctrl$nonASCII] }
+;
my $atom = qq{ $atom_char+ };
my $byte = qq{ (?: 1?$digit?$digit |
2[0-4]$digit |
25[0-5] ) };
my $qtext = qq{ [^$esc$nonASCII$CRlist"] };
my $quoted_pair = qq{ $esc [^$nonASCII] };
my $quoted_str = qq{ " (?: $qtext | $quoted_pair )* " };
my $word = qq{ (?: $atom | $quoted_str ) };
my $ip_address = qq{ \\[ $byte (?: $dot $byte ){3} \\] };
my $sub_domain = qq{ [$letter$digit]
[$letter$digit-]{0,61} [$letter$digit]};
my $top_level = qq{ (?: $atom_char ){2,4} };
my $domain_name = qq{ (?: $sub_domain $dot )+ $top_level };
my $domain = qq{ (?: $domain_name | $ip_address ) };
my $local_part = qq{ $word (?: $dot $word )* };
my $address = qq{ $local_part \@ $domain };
return $addr_to_check =~ /^$address$/ox ? $addr_to_check : "";
}
