types.add(new SelectItem(IContentListFilterAction.METADATA_KEY_PREFIX + IContentManager.CONTENT_MODIFY_DATE_FILTER_KEY, this.getText("label.lastModifyDate")));
      //String contentType = this.getShowlet().getConfig().getProperty(IContentListWidgetHelper.WIDGET_PARAM_CONTENT_TYPE);
      Content prototype = this.getContentManager().createContentType(this.getContentType());
      List<AttributeInterface> contentAttributes = prototype.getAttributeList();
      for (int i=0; i<contentAttributes.size(); i++) {
        AttributeInterface attribute = contentAttributes.get(i);
        if (attribute.isSearcheable()) {
          types.add(new SelectItem(attribute.getName(), this.getText("label.attribute", new String[]{attribute.getName()})));
        }
      }
    } catch (Throwable t) {
      ApsSystemUtils.logThrowable(t, this, "getAllowedFilterTypes");
      throw new ApsSystemException("Error extracting allowed filter types", t);