Arrow Keys and Backspace stop working in Flash Builder or Eclipse

I just ran into a problem SO annoying, I had to stop EVERYTHING and write down how to fix this, immediately. That way, the next time it happens, I won't pull the rest of my hair out!

Problem

Suddenly, the arrow keys and backspace button stop working in Flash Builder or Eclipse.

Symptoms

• Arrow keys don't work in Flash Builder
• Arrow keys work fine in other applications
• Backspace key does nothing
• Opening and closing Flash Builder or Eclipse doesn't necessarily fix the problem.

Solution

It's odd but to fix this, you just have to click every mouse button. For me, the problem went away as soon as I left-clicked.

I found the solution here:
http://board.flashkit.com/board/showthread.php?t=798172

Where the problem is described as:

"It seems to be a mouse driver issue. Sometimes the program will register one of the mouse buttons as stuck. To fix it, I have to press each button until it works again.

Apparently it was fixed in the new eclipse, but flex which is based off eclipse never fixed this bug."