<parameter name="my-param" type="string">
     <label i18n="true">I18N_KEY_LABEL</label>
     <description i18n="true">I18N_KEY_DESC</label>
     <enumeration>
	<custom-enumerator class="org.ametys.cms.workflow.DefaultWorkflowStepEnumerator"/>
     </enumeration>
     <widget>sorted-enumeration</widget>
     <widget-params>
         <param name="emptyText" i18n="true">plugin.cms:WIDGET_COMBOBOX_ALL_OPTIONS</param>
     </widget-params>
</parameter>