UPDATE_COMMAND_UI handling

Within a simple dialog program I want to gray out or darken certain main menu pull down items based on the current state of program
execution. I have implemented this functionality in a MDI aplication where I tied a simple hander to the UPDATE_COMMAND_UI
message for the menu item to be manipulated. This worked just fine with the handler called as the user opened the specific pull-down,
but before the sub items are displayed which is perfect for deciding to darken an item or to gray it.

I have tried to implement the same functionality in my dialog base application, but it appears that the handler is not called until after the pull
down menu items have been displayed. This is to late. I don't completely understand the framework differences between dialog based
applications and document view applications to understand what is different in handling the UPDATE_COMMAND_UI message or if
it even makes sense to handle it in a dialog application. However, graying out menu items seems like such a fundamental thing to do
that there must be a correct way to do it in a dialog application. Any ideas?

look at http://www.codeguru.com/dialog/OnUpdate.shtml