QUOTE (clementgirod @ May 11 2009, 12:23 PM)  
 
Hi, 
You must be able to handle windows messages, 
Whe a window is inactive and you click inside it, the OS sends to the window the message WM_MOUSEACTIVATE and the window 
must reply this message with MA_ACTIVATE, MA_NOACTIVATE or MA_ACTIVATEANDDEAT.  
In your case you must use MA_NOACTIVATE. 
I dont know how to disable alt+tab too. 
Bruno.