Bug InputManager Vertical Axis sticks at maximum positive or negative value

In Build #2015091501 editor play mode, the first time the up or down arrow key is pressed, the input manager vertical axis value increases to and sticks at the maximum value (1 or -1); as if the user has continued to press the key. This does not happen when using the s or w keys or with the horizontal axis. This did not happen with Build #2015082501 (I never tried Build #2015090301), and it does not happen in the built project.

 

Already reported here: http://forum.unity3d.com/threads/arrow-keys-get-stuck-when-you-press-them.356479/