[Zope] logged_out from CookieCrumbler

One of my sites uses frames. User management uses the CookieCrumbler. When a user logs out, a logged_out dtml-method is invoked. The logged_out method kills off session and browser information and then transfers to the initial splash screen which links to the login page which includes the login page in the frameset. When the user logs out, the splash screen is rendered in one of the frames of the frameset rather than replacing the frameset. What's the magic needed?