Dialog not popping-up

[andrew . w . wooster]

I have not been able to get modal dialogs to pop-up.  I see them working 
in the adf-faces-demo, but I cannot get them to work in my code.  Here's 
what I'm doing:

In Header.jsp:
  <af:form>
    <af:commandLink id="cmdLink" text="Lists" action="dialog:ListCatalog" 
useWindow="true"/>
  </af:form>

In faces-config.xml:
  <navigation-rule>
    <navigation-case>
      <from-outcome>dialog:ListCatalog</from-outcome>
      <to-view-id>/portal/ListCatalog.jsp</to-view-id>
    </navigation-case>
  </navigation-rule>

If I drop the "dialog:" prefix, the browser will redirect to 
ListCatalog.jsp, but will not pop-up a new window.  What am I missing?
-Andrew