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      <handler

            class="eu.etaxonomy.taxeditor.editor.handler.defaultHandler.DefaultOpenTaxonEditorForTaxonHandler"

            commandId="eu.etaxonomy.taxeditor.editor.openTaxonEditorForTaxon">

         <activeWhen>

            <and>

               <not>

                  <reference

                        definitionId="isOrphanedTaxon">

                  </reference>

               </not>

            </and>

         </activeWhen>

      </handler>