Implementing SQL Application Roles with Site-Map Security Trimming with the Navigational Menu Component

 I have an asp.net application using SQL Application Roles, which works as needed.  The users are authenticated by their WINNT. 
Now, I would like to use ASP.NET Site-Map Security Trimming with the Navigational Menu Component for security.  Reading the following, http://msdn.microsoft.com/en-us/library/ms178428.aspx, talks about how to use Microsoft Roles, but not SQL Application Roles.
I have tried the following and the user can view the web page.  I appreciate the assistance.
Thank you.
My code is:
Web.Sitemap  
 <?xml version="1.0" encoding="utf-8" ?>
    <siteMap>
      <!-- other <siteMapNode> elements -->
      <siteMapNode title="People" description="People"
&nb ...