How is it posible to enable a default sort field in weblink gridview using the object weblink:SearchResultsBrowser on the Search.aspx file? like the object weblink:searchresultsbrowser8, as shown below:

<weblink:searchresultsbrowser8
	 SortableColumns="COLUMN_TYPE_LASTDATE, COLUMN_TYPE_CREATEDATE"    SortableFields="REG - Acto"
	 DefaultSortField="REG - Acto"
	 AdditionalProperties="COLUMN_TYPE_CREATEDATE, COLUMN_TYPE_LASTDATE, COLUMN_TYPE_NUMPAGES, COLUMN_TYPE_TAGS"
	 ThumbnailCount="5"
	 id="TheSearchResultsBrowser" runat="server" width="100%" MaxLength="10" />

<div style="display: table; table-layout: fixed; width: 100%;">
	<%-- Set Enabled to true if using grid view; otherwise, set it to false for list view --%>
	<weblink:SearchResultsBrowser
		SortableColumns="COLUMN_TYPE_LASTDATE, COLUMN_TYPE_CREATEDATE"    SortableFields="REG - Inscripcion"                                                                                                                                            
		id="TheSearchResultsBrowserGrid" runat="server" width="100%" MaxLength="10" Enabled="true" />
</div>