code: public void setValign(String valign) {
          /* todo: should this enforce top|middle|bottom|baseline as in the spec */
          _theadTag.registerAttribute(AbstractHtmlState.ATTR_GENERAL, HtmlConstants.VALIGN, valign);
      }
docs: Sets the value of the vertical alignment attribute rendered by the HTML thead tag.
  
  @param valign the vertical alignment
  @jsptagref.attributedescription The vertical alignment rendered by the HTML thead tag
  @jsptagref.attributesyntaxvalue <i>string_align</i>
  @netui:attribute required="false" rtexprvalue="true" description="The vertical alignment rendered by the HTML thead tag.