UiDoc page outline issue

I noticed something very strange in the Notes Outline. We used embedded outlines on a page, and used that page in a left frameset as navigator. I created an agent attached to a view action button and in that I am checking for UiDoc for my special purpose (not writing here why I want to do that). I know that when a user highlighted a doc in the view and run this agent, the uiDoc object should be nothing; surprisingly, the script is identifying the outline page as UIDoc object.

I did some further testing on it and found that if I use default outline instead of my custom one, there is no UIDOC object which is correct.

Any ideas? solutions? Has anyone noticed this in prior versions?

Thanks, Yesu