How to keep the mouse contained to the guest OS?

[WhiteBear]

Hi,
I have a WinXP guest installed inside Win7 64 bit host in VB 4.2.6
I installed the Guest Additions but I would like to turn off the seamless mouse integration at certain times - especially when I try a game inside the guest OS.
Then I need the mouse to move only inside the guest OS window.
I can't really play a game because many times when I move the mouse it will exit the guest window OS and when I click I activate a window on the host system.
Is there any setting for that?

Thanks

[WhiteBear]

I found it, on the bottom-right corner of the VirtualBox window there is a button with a mouse icon on it. Right click - Disable mouse integration (Host + I)