Close this stack vs. clicking the close button

[Bill Vlahos]

If I click the close box of a window I am able to handle everything  
fine.

I have a "Close" menu item which I've tried "close this stack", "send  
closeStack to this stack in 1 millisecond", and "send closeStack to  
the long name of this stack".

The closeStack handler gets the message because it prompts the user to  
save the changes. However, after that it doesn't behave the same.

What is different between clicking the close box and issuing the  
command?

Bill Vlahos