Differentiate user form close and OS close

Hi,

Im developing a Pocket PC application with VB.NET using multiple forms
inspired by the FormStack example:
http://msdn.microsoft.com/library/de...iframework.asp

Hovever I reached a point where i cannot find any solution. The applications
main form is a "minimize" type form the other forms like options are "close"
type forms.

When a user closes one of the option type forms the form close is actually
canceled the window hides and the previous form from the stack shows up.

This works perfectly however when the application is shut down from the
Running Programs List it claims the program is not responding when the
active form is a form other than the main form.

So is it possible to see if a close event is rised by the OS or by the user
by clicking the close button?

I found something about WM_QUIT and PostQuitMessage, but im not sure about
how to go on. Is it possible to query if the application is set to shut down
or is it possible to rise an event?

Thanks in advance

Sune Pedersen