sub valid_address {
        my @testmail;
        my $data;
        my $test;
        my $flag = 0;
        ($data) = @_;
        @testmail = split('\,',$data);
        if ($data !~ /,/) {
                $testmail = $data;
        }
        foreach $test (@testmail) {
                if ($test=~ /(@.*@)|(\.\.)|(@\.)|(\.@)|(^\.)/ || $test!~ /^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,5}|[0-9]{1,5})(\]?) $/ ) {
                        $flag = 1;
                }
                else {
                        $flag = 0;
                }
        }
        if ($flag) { return 0; }
        else { return 1; }
}