} elsif ( $tagslib->{$tag}->{$subfield}->{value_builder} ) {

                        # opening plugin

                        my $plugin = C4::Context->intranetdir . "/cataloguing/value_builder/" . $tagslib->{$tag}->{$subfield}->{'value_builder'};

                        if (do $plugin) {

                            my $temp;

                            my $extended_param = plugin_parameters( $dbh, $temp, $tagslib, $subfield_data{id}, undef );

                            my ( $function_name, $javascript ) = plugin_javascript( $dbh, $temp, $tagslib, $subfield_data{id}, undef );

                            $subfield_data{random}     = int(rand(1000000));    # why do we need 2 different randoms?

                            my $index_subfield = int(rand(1000000));

                            $subfield_data{id} = "tag_".$tag."_subfield_".$subfield."_".$index_subfield;

                            $subfield_data{marc_value} = qq[<input tabindex="1" id="$subfield_data{id}" name="field_value" class="input_marceditor" size="67" maxlength="255"

                                onfocus="Focus$function_name($subfield_data{random}, '$subfield_data{id}');"

                                 onblur=" Blur$function_name($subfield_data{random}, '$subfield_data{id}');" />

                                <a href="#" class="buttonDot" onclick="Clic$function_name('$subfield_data{id}'); return false;" title="Tag Editor">...</a>

                                $javascript];

                        } else {

                            warn "Plugin Failed: $plugin";

                            $subfield_data{marc_value} = qq(<input tabindex="1" id="$subfield_data{id}" name="field_value" class="input_marceditor" size="67" maxlength="255" />); # supply default input form

                        }

                }

                elsif ( $tag eq '' ) {       # it's an hidden field

                    $subfield_data{marc_value} = qq(<input type="hidden" tabindex="1" id="$subfield_data{id}" name="field_value" class="input_marceditor" size="67" maxlength="255" value="$defaultvalue" />);

                }

                elsif ( $tagslib->{$tag}->{$subfield}->{'hidden'} ) {   # FIXME: shouldn't input type be "hidden" ?

                    $subfield_data{marc_value} = qq(<input type="text" tabindex="1" id="$subfield_data{id}" name="field_value" class="input_marceditor" size="67" maxlength="255" value="$defaultvalue" />);

                }

                elsif ( length($defaultvalue) > 100

                            or (C4::Context->preference("marcflavour") eq "UNIMARC" and

                                  300 <= $tag && $tag < 400 && $subfield eq 'a' )

                            or (C4::Context->preference("marcflavour") eq "MARC21"  and

                                  500 <= $tag && $tag < 600                     )

                          ) {

                    # oversize field (textarea)

                    $subfield_data{marc_value} = qq(<textarea tabindex="1" id="$subfield_data{id}" name="field_value" class="input_marceditor" size="67" maxlength="255">$defaultvalue</textarea>\n");