Question about focus change.

Hi,

I'm a developper from the Ka-ra team. I have a problem with focus on wpf.
The focus in wpf seems to not have the same behavior than windows.
In fact, in winform, if you put a simple textbox on a window, you can give the focus to the textbox on click on it, and loose the textbox focus on click everywhere else on the window.
But in wpf, I can't have this behevior... If you click on the window, the textbox keep the focus...
Anybody have an idea to change that ?

Thanks,
Cedric