It turns out that Compatability Mode causes issues with Facebook's Recent Activity Widget, so it really is not a viable option for us as we use both Recent Activity widgets and Like Boxes on the same page. In addition, Facebook appears to be making progress in addressing the issue with the Like Box. Based on the fact that after several days the only offerred solution does not address our actual request, I have to assume that there is no way to dynamicaly activate the Compatability Mode button.
