I am running mountain lion on an iMac. I have noticed that if I have, for example, Mail and Safari both open and try to switch from one to the other by clicking inside the program window (i.e., I have Safari active and I get an email so I click in the messages area of Mail to switch to Mail) my keyboard freezes.
The problem does not occur if I switch between by clicking on the program header (i.e., the gray toolbar at the top). It also switches fine using cmd+tab.
I can unfreeze the keyboard by switching back to the original program and clicking on its header bar. When I do this it moves the windows around on the desktop on its own.
Never had it happen on Snow Leopard. Any thoughts or suggestions?
Thanks.

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