Like choroba says it should work, but,

What webserver are you using (mapache moo.A.1245?? ) What CGI.pm are you using?

Hehehe, CGI.pm, never ceases to confuse :) delete this stuff from your program

### use CGI qw(:standard); ## REMOVE MYSTERY CODE
### use CGI 'param';       ## REMOVE MYSTERY CODE
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Then try this program in your browser and see what you get

#!/usr/bin/perl --
use strict;
use warnings;
use CGI;
my $store = CGI->new;
my $cell = $store->param('cell');
my $target_dir = $store->param('target_dir');
print $store->header;
print $store->escapeHTML( $cell );
print '<hr>';
print $store->escapeHTML( $target_dir );
print '<hr>';
DebugCGI( $store);
exit 0;


sub DebugCGI {
    my( $cgi ) =  @_;
    $cgi ||= CGI->new;
    binmode STDOUT, ':encoding(UTF-8)';
    $cgi->charset( 'UTF-8' );
    print $cgi->header( -charset => 'UTF-8' );
    print $cgi->start_html,
      $cgi->b( rand time, ' ', scalar gmtime ),
      '<table border="1" width="%100"><tr><td>',
      $cgi->Dump,
      '</td>',
      '<td><div style="white-space: pre-wrap; overflow: scroll;">',
      $cgi->escapeHTML( DD( $cgi ) ),
      '</div></td></tr></table>',
      CGI->new( \%ENV )->Dump,
      $cgi->end_html;
} ## end sub DebugCGI

sub DD {
    require Data::Dumper;
    return scalar Data::Dumper->new( \@_ )->Indent( 1 )->Useqq( 1 )->D
+ump;
} ## end sub DD


__END__
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Take special note of the value of QUERY_STRING