trouble with optional and required fields in a form

I have this script from an e-mail form:

#!/usr/local/bin/perl

$|++;      ##      Disable output buffering.

use CGI;

$q=new CGI;

$err_ctr=0;      ##      Initailize the error count.

##      Read the incoming HTML variables into Perl variables.
##      The Perl variables have the same name as the HTML form variables.
foreach ($q->param){
      $$_=$q->param($_);
      $$_=~ s/^\s+//g;
      $$_=~ s/\s+$//g;

      if (/^cp$/ || /^celular$/ || /^tel_oficina$/||/^extension$/|| /^dia_hora_entrega$/){
 next;      ##      Ignore this optional field.
      if (!($$_)){      ##      Check if any of the mandatory fields are empty.
            print "Content-type: text/html\n\n" if (!($err_ctr));
            print "<B><FONT COLOR=RED>$_ cannot be empty.</FONT></B><BR>\n";
            ++$err_ctr;      ##      Increment the error count.
      }else{
            ##      Build the plain text message of the email.
            $plain_text.=$_." = ".$$_."\n";
            #print $_," = ",$$_,"<BR>\n";
      }
}

if ($err_ctr){      ##      We do have some error messages!!
      exit;      ##      Bail out!!
}

$boundary="Message-Boundary-19990614";
$from='Web<>';

push(@attachments,$file);

##      Prepare to send out the email to you, the owner of the site.
$mailprog ="/usr/lib/sendmail";
open(MAIL, "| $mailprog -t ") || die "Content-type: text/html\n\n$!";
print MAIL "To: $recipient\n";
print MAIL "From: $from\n";
print MAIL "Subject: $subject!\n";
print MAIL "MIME-Version: 1.0\n";
print MAIL "Content-type: Multipart/1;\n";
print MAIL "\tboundary=$boundary\n";
print MAIL "\n";
print MAIL "\n";
print MAIL "--$boundary\n";

##      Add the plain text message to the email
if ($plain_text){
      print MAIL "Content-type: text/plain; charset=US-ASCII\n";
      print MAIL "Content-description: Mail message body\n";
      print MAIL "Content-transfer-encoding: 7BIT\n";
      print MAIL "\n";
      print MAIL $plain_text."\n";
      print MAIL "--$boundary\n";
}

##      Attach all the files to the email
foreach $file (@attachments){
      undef $some_text;

      ##  Read 1024 bytes at a time
      while($bytesread=read($file,$data,1024)){
            $content.=$data;    ##  Store the ACTUAL file content
      }
      close($file);

      $some_text=&encode_base64($content);

      ##      Convert all \'s to /
      $file=~ s/\\/\//g;

      ##      Extract the name of the file.
      $file=~ /.*\/(.*)/;
      $actual_file=$1;

      ##  Print the header for that attachment.
      print MAIL "Content-type: application/octet-stream; name=\"".$actual_file."\"; type=Unknown\n";
      print MAIL "Content-transfer-encoding: BASE64\n";
      print MAIL "Content-disposition: attachment\n";
      print MAIL "\n";
            
      ##  Send out the contents!!
      print MAIL $some_text;
      print MAIL "\n";
      print MAIL "--$boundary\n";
}

##      Send the Email!!
print MAIL "--$boundary--\n";
close(MAIL);

##      Prepare to send out the "Thank you" email to the user.
$mailprog ="/usr/lib/sendmail";
open(MAIL, "| $mailprog -t ") || die "Content-type: text/html\n\n$!";
print MAIL "To: $E_MAIL\n";
print MAIL "From: $from\n";
print MAIL "Subject: Gracias por llenar nuestro formulario. \n";
print MAIL "Estimado usuario:\n\nSu información ha sido recibida.\nEn breve nos comunicaremos con usted.\n\nAtentamente\n\nSelective Directory";
print MAIL "\n";
close(MAIL);

##      Now redirect the user to some page.
print "Location: $redirect\n\n";

sub encode_base64 ($;$){
  my $res = "";
  my $eol = $_[1];
  $eol = "\n" unless defined $eol;
  pos($_[0]) = 0;                          # ensure start at the beginning
  while ($_[0] =~ /(.{1,45})/gs) {
    $res .= substr(pack('u', $1), 1);
    chop($res);
  }
  $res =~ tr|` -_|AA-Za-z0-9+/|;               # `# help emacs
  # fix padding at the end
  my $padding = (3 - length($_[0]) % 3) % 3;
  $res =~ s/.{$padding}$/'=' x $padding/e if $padding;
  # break encoded string into lines of no more than 76 characters each
  if (length $eol) {
    $res =~ s/(.{1,76})/$1$eol/g;
  }
  $res;
}


but it sends an error:

Missing right curly or square bracket at /home/cgi-bin/head_hunters1.pl line 129, at end of line
syntax error at /home/cgi-bin/head_hunters1.pl line 129, at EOF
Execution of /home/cgi-bin/head_hunters1.pl aborted due to compilation errors.

the only part of the script I changed is the one about optional fields:

if (/^cp$/ || /^celular$/ || /^tel_oficina$/||/^extension$/|| /^dia_hora_entrega$/){
next;     ##     Ignore this optional field.

but if I write this instead:

next if /^cp$/;
next if /^celular$/;
next if /^CP$/;
next if /^tel_oficina$/;

it doesn´t sends an error, and it doesn´t ask for the fields to be filled, but if I fill them when I receive the email from the form the information from those fields don´t appear in it