[O] Org-class: recurring appointments not being displayed

[knubee]

I have tried variations of the two examples for recurring
appointments (that last for a limited period of time) shown here:

http://orgmode.org/worg/org-faq.html#org-class

But neither of them result in any appointment being displayed in
agenda.

Examples:

* Class 7:00pm-9:00pm
   <%% (org-class 2011 1 10 2011 4 10 2 8)>
* Class
%%(org-class 2011 1 10 2011 4 10 2 8) 7:00pm-9:00pm Class

These examples were entered into my todo.org file; other entries
in the file display just fine in the agenda.

Is this working for others? If so, any suggestions?

I am using the latest cvs version of emacs and recently-updated
version 7.8.3 of org-mode.