Showing Headings in Top Navigation Fly-out Menus

I have been fighting with the bad magic that is SharePoint recently, and one of the (many) problems I was having is that the design called for Headings to show up in the drop down menus, but we just could not get them to show up. It was very difficult to find information on this, mainly because there are so many options and configuration choices for a SharePoint site that few solutions are ever straightforward or even applicable to how you have the site set up. I never found a direct explanation of how to get Headers in the drop down (flyout) menus, but luckily I found the solution by chance on a page explaining something else.
The first step is to make sure your site is set up correctly to use drop down menus. This article provides a good explanation. If you are just using WSS 3.0 instead of MOSS 2007, you will likely have to look somewhere else, as I’m pretty sure this will only work with the full product.
Once your site is set up, it’s easy to build out nice looking menus using the Navigation page in the Site Settings, but the headings won’t show up on the drop downs, at least with a Team Site Collection, it may be different with some of the other site types.
These changes need to be made to the master page you are using for the site, and to the administration master page if you want it to show up the same on those pages.
Add the following to the top of the page, under the other control declarations:

<%@ Register Tagprefix="PublishingNavigation" Namespace="Microsoft.SharePoint.Publishing.Navigation" Assembly="Microsoft.SharePoint.Publishing, Version=12.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c" %>

Add this right under the first SharePoint:ASPMenu‘s closing tag:

<publishingnavigation:PortalSiteMapDataSource ID="siteMapDataSource1" Runat="server" SiteMapProvider="CombinedNavSiteMapProvider" EnableViewState="true" StartFromCurrentNode="true" StartingNodeOffset="0" ShowStartingNode="true" TreatStartingNodeAsCurrent="true" />

Change the DataSourceID in the SharePoint:AspMenu control to siteMapDataSource1.
That’s it. Your Headings should now show up in the top navigation drop down menus.