When you installing Ubuntu in your Macbook Pro, then you will realize that F11 and F12 doesn't works very well.
F12 will be trigger right click which it may conflicting with yakuake. Even you use Ubuntu 12.04 Precise Pangolin, this still happen.
It's not bug anyway.
So, why this is happen? then you can blame "mouseemu" package.
To solve this problem, just uninstall mouseemu :
1. From Synaptic
Search "mouseemu" and remove / uninstall this packages.
2. From command-line
sudo apt-get remove mouseemu