How to make toplevel app window with transparent image?

[Rodrigo Senra]

Does anybody know how to create a GUI app (any tool but I prefer Tkinter
or wxWindows)
where the toplevel frame consists of a transparent gif ? Could the
possible
solution be portable ?

Explanation: I'm planning to build a GUI app where the main windows is
not
rectangular,but has a shape given by some image. I need to make the
'transparent'
parts of such image truly hollow. 

Any pointers?
TIA
Rod
-- 
Rodrigo Senra         
Computer Engineer   (GPr Sistemas Ltda)  rodsenra at correionet.com.br 
MSc Student of Reflection (IC- UNICAMP) Rodrigo.Senra at ic.unicamp.br
http://www.ic.unicamp.br/~921234 (see also   http://www.gpr.com.br)