Possible to lock mouse to one window?

I'm currently two boxing and getting the hang of it.
With my configuration i'm using keyclone with a 22" widescreen on a 90 degree tilt to get the best of the screen. However i've got my main down below with the alt on top.
The issue i've been having is I tend to use a pretty fast mouse and generally when i'm zipping around on screen it will drift upwards to the alt and make it active, thus creating some lag (baaad in combat)
Is it possible to setup some sort of hard dimensions for the mouse? And have the ability to perhaps use the swap screen function of keyclone/maximizer to put the mouse in the other window?
It's not a huge deal, but is getting a touch annoying! Can't seem to find anything related to this.

I have my 4 slaves on 22" rotated screens and I have found that if you disable focus follows mouse in keyclone, it doesn't matter if you mouse over the windows anymore as you have to click in the window to activate it.