Powerpoint 2007 Beta 2 : context menu not created by plugin

Hi,
We are adding a plugin in Office (powerpoint, word, Excel and Outlook) and
everything works fine for Office 2003 and lower versions.
With Office 2007, we have an issue with powerpoint where the context menu
associated with our functions is not created. For Word, Excel and Outlook, it
works fine. My problem is that we are using the same code to load the context
menu items for each application (our base plugin class is doing it).

All we are doing is adding buttons to our popup command bar.

Does anybody have an idea or has encountered the same problem ?

Olivier