code: public String dialogBlock(int segment, String headline, boolean error) {
  
          if (segment == HTML_START) {
              StringBuffer result = new StringBuffer(512);
              String errorStyle = "";
              if (error) {
                  errorStyle = " dialogerror";
              }
              result.append("<!-- 3D block start -->\n");
              result.append("<fieldset class=\"dialogblock\">\n");
              if (CmsStringUtil.isNotEmpty(headline)) {
                  result.append("<legend>");
                  result.append("<span class=\"textbold");
                  result.append(errorStyle);
                  result.append("\" unselectable=\"on\">");
                  result.append(headline);
                  result.append("</span></legend>\n");
              }
              return result.toString();
          } else {
              return "</fieldset>\n<!-- 3D block end -->\n";
          }
      }
docs: Builds a block with 3D border and optional subheadline in the dialog content area.<p>
  
  @param segment the HTML segment (START / END)
  @param headline the headline String for the block
  @param error if true, an error block will be created
  
  @return 3D block start / end segment