Re-attaching tab to notebook via "close" event

[Ryan Taylor <ryta1203 gmail com>]

If I take a page from a notebook (a tab from a notebook) and move it, it creates a window.

What I want is to take all the pages from the new window and re-insert them into the old notebook when a close event occurs (ie the X exit or File->Close).

What is the best way to accomplish this?

Thanks.