How to disable window size management due to a mouse double click ?

Hi everybody,

I have a small problem. I have an application whose main window can be maximized or minimized (in fact it is restored in the default minimum size) after the user double click the title bar.

I must disable this behaviour because the application's main window must not be resized neither moved.

What I did is :
* set the size policy to fixed
* set the fixed size

It half works because the application is not resized anymore but it is still moved ... the upper left corner of the application's main window is moved to the upper left corner of the screen.

It is a big application, not well designed so the method are not usually at the good place so it hard to find them ... especially because I am not sure what method to find :o

So, here are my questions :
* what must I disable to respond to my need ?
* which methods are called ?
* which slots / signals / event should I look at in the code ?

Thanks by advance.