StayOnTop forms - question

hi,
In my little program I have two forms: the main one and the mini one. I
would like the mini_form to stay on top of all other windows.
The problem is:
when I set the forms style to fsStayOnTop the mini form stays on top of the
main form but not on top of any other window.
How to create a global StayOnTop form ?

Thanks
Majkel

P.S.
I have tried
 SetWindowPos(mini_form.handle,
   HWND_TOPMOST,mini_form.Left,
   mini_form.Top,  mini_form.Width,
   mini_form.Height,0)
but this does exactly the same thing.