I have faced this problem before....
just go to the menu right click on it ,
say add event handler, Add the ONUpdate
event handler. U will have to enable
Every menu, Sub Menu OnUpdate event handler.
Then its quite simple use the pCMdUI->enable()
method to enable / Disable menu depending upon the condition.
The other method is to create a pop up menu , where the
enabling and disabling of menus will be simpler.
Hope i have solved u r problem , if not reply back here